Tony Blair ought to step down for the next election, Clare Short has said after quitting as International Development Secretary.
Mr Blair had achieved an "enormous" amount and it would be "very sad if he hung on and spoiled his reputation" she told newspapers on Tuesday.
Ms Short accused the prime minister of being "reckless" over his policy on Iraq and in her resignation letter, suggested Mr Blair had broken his assurances on the United Nations role in governing post-conflict Iraq.
What is your reaction to Clare Short's resignation? Should Tony Blair step down? Should Ms Short have stepped down herself before now?
Thank you for your e-mails. This debate is now closed. A selection of your comments is published below.
The following comments reflect the balance of views we have received:
She was naive enough to trust Tony Blair and he was naive enough to trust George Bush.
JOHN M, UK
Despite the fact that I agree with what she said, as do a lot of people, she has gained no respect from me. It was only a few weeks ago she said she would quite if we went to war with Iraq - what stopped her? Why didn't she stick to her words then or was it all said in haste.
If Tony Blair should ever step down, Labour will lose the following election. In the last two elections, do you think the electorate voted for New Labour, whatever that was? No way, it was a personal vote for Mr Blair.
Clare Short accuses Tony Blair of behaving like a president and ignoring parliament and the electorate, and then resigns. Blair issue scornful denials of all the charges - then appoints a non-elected replacement.
Well done. Giving up a job is never easy and everybody is now and then allowed to hesitate between personal and moral interests. She's doing well to show Blair and Straw that they have gone off the rails.
Phil, Bristol. England
Clare Short's political inconsistencies have been well publicised down the years so the Blair government will not be weakened by her departure. However, her departure may signal the beginning of the end of Blair's Camelot. It looks as if the UK and Europe are about to follow America's right turn. That said, the UK's, USA's and EU's current economic and fiscal policies are leading the world into a bigger mess than anything Osama bin Laden or Saddam Hussein have ever managed to achieve.
Dr David Green, Greece
Her vacillation revealed her as local politician rather than international statesperson. In the end no-one could give her credence because she lost belief in her own judgement.
Clam, Hong Kong
Maybe Galloway will lend her his villa for a well earned holiday.
Blair should have stepped down a while ago! He hooked himself to Bush's wagon and he shouldn't have. There is NO honour in what happened in Iraq nor in the agenda that propelled it¿ the greed for oil! I salute Clare Short. The world needs more political people with scruples and morals!
Pat Schmit, Costa Rica
She was key in keeping Uganda & Rwanda from coming to blows - A diplomat... is a person who can tell you to go to hell in such a way that you actually look forward to the trip.
It seems amazing that it's taken so long, either for her to quit or be moved on. I don't doubt her beliefs are genuine, but as a Cabinet member she must understand that politics requires a degree of discretion. She was a champion for the left, fighting for their causes at No.10, now she will just be another back-bencher like Cook, whining in the wasteland.
This is indeed the saddest day for me and people who believe in international consensus building! Africa and indeed the developing world has lost a great friend. Hon Claire Short you remain my hero!
Julius Mure, UK
For the second time this year Clare Short has been carried away with a sense of her own importance. She thought it mattered that she stayed on two months ago, and now she thinks it matters that she is resigning. She has been wrong on both occasions. I'm sure Baroness Amos will do the job equally well but without the histrionics.
I have to admit I was disappointed she backed out before the start of the war. But feel that at this point her resignation does something very important: it highlights the hugely significant issues arising from the so-called "reconstruction of Iraq" part of the deal - which isn't talked about. Well, at least not until now that Short has resigned.
Clare Short has at last stood up for her principles. Mr Blair has shown in his actions that his faith in the UN no longer exists. Ms Short believed in a post UN led Iraq, this is not going to happen. Bush and Blair are now the heads of state for Iraq. As Blair said, "history will be my judge". The jury is now starting to speak.
Nick Harris, England
I simply think she is now in the best place for her talents: on the backbenches offering a moral and knowledgeable point of view on international development and other issues. I always felt she was out of place in a government position and now she may do what she was born to do: oppose.
Clare Short has represented sane and rational thought throughout the situation in Iraq. She opposed this unnecessary war from the outset but controversially, like the British public, felt that she needed to support the troops and the reconstruction of Iraq. Like a large percentage of the population she feels that she has been betrayed by Blair. Clare Short deserves our respect.
Jamie Merrill, UK
I think that if she feels she has to resign, then it's right for her to do so. Whether anyone agrees with her reasoning or not, if she doesn't feel that she can do her job under the current circumstances, then staying on wouldn't serve any purpose. It's hard to work for someone you've lost your faith in.
Andy Kitching, Leeds, UK
When she realised that her country has been taken for ride by her prime-minister and United states, she resigned. That's the only step in my opinion any person with a self respect would take in the current circumstances.
Tushar Patil, India
As a Labour Party member, I am sure that her analysis of how policy is formulated by the "Number 10 inner sanctum" is largely correct. Unfortunately for her, it was clearly also the case seven or eight weeks ago when she first threatened to resign. Does she really believe that her speech today will re-establish her credentials?
Robert Crosby, Nottingham, UK
Short's big mistake was believing the assurances about the UN while Blair was pleading with her not to resign. She was misled and resigning and calling attention to her reasons are the right things to do. I wish there were more people in the US with similar backbone.
Mary Golden, USA
Clare Short is a woman with a conscience but also a sense of realpolitik. I think the fact that she has resigned now shows the increasingly questionable values and aims of this government.
Owen James, UK
I hope and pray she 'gives them hell' from the back benches... That is what she should have been doing from the outset anyway! Her conscience came first, albeit a little late. WELL DONE, Clare!!!
Clare Short (no relation), Scotland, UK
At the end of the day, Clare Short had just lost too much political credibility. The war in Iraq was a success, and no-one was more pleased than the ordinary Iraqis. She could have stayed and rebuilt her reputation, but she has now consigned herself to political exile.
Guy Hammond, England
I am sad to see one of the few in Parliament I would trust at all. She is a down to earth woman of compassion and integrity. She will be greatly missed from her post. I hope we see her back again in other circumstances.
Clare Short is right to point out Bush and Blair's lies about rebuilding Iraq, but it's difficult to feel any sympathy for someone who copped out of a resignation that might have stopped UK involvement in a criminal, imperial occupation. The idea that her continued presence would do anything to offset the oil-grabbing, asset-stripping neo-liberal project now under way was unmitigated egotism. The truth is she fought with her conscience and won.
Andrew Stone, UK
The phrase 'Better late than never' springs to mind. Although I feel she should have resigned earlier, in a way the timing may be more effective now as it has brought back into the open this mess which now seems to be getting very little publicity. I just wish President Blair would do the same... Well done Clare.
Aquil Khan, England
Her behaviour over the whole Iraqi affair has been erratic to say the least. I imagine she has few friends left on either side of the divide but if she can provide the public with a frank insider's account of this government's inconsistencies and misdealings (if they have made any as most people suspect) then I'm prepared to give her a second chance.
James Loginov, Great Britain
All the respect I had for Clare Short has disappeared. If she felt so strongly about Iraq she should have left when the conflict started. Instead, the promises made have evaporated. But it doesn't take an expert to realise that. Most of the world knew there would have been a conflict as soon as George Bush announced the 'axis of evil'. Unfortunately Clare Short was too interested in power and the luxuries that come with it.
Neil Woollcott, England
It's a real shame that a woman elected to represent the people of this country has effectively been hounded out of her job for doing just that. We've also lost one of the most honest and hard-working cabinet members. Soon all we'll be left with is a House of Commons brimming with gutless politicians too scared of losing their jobs to stand up to Blair.
Clare Short did an excellent job in turning the Department for International Development into a high-profile ministry. She had good relations with Gordon Brown and persuaded him and the government to double DFID's budget. I had complete sympathy with her not resigning earlier, even though she would inevitably get flack from all sides - imagine a humanitarian crisis as serious as Iraq, and a secretary of state who'd been in the post just a couple of weeks. I interpreted her decision to stay as sacrificing her career for the sake of promoting the best possible humanitarian response. All respect to Clare.
I am actually glad that Claire Short has chosen this moment to resign as it highlights the fact that the US/UK coalition had no real plans for the reconstruction of Iraq. Post-conflict Iraq is still in tatters and the UN are being held back from doing anything about it. If this is not proof that we were wrong to go to war in the first place, I don't know what is.
Brian Docherty, UK
The downside of any principle-based cabinet resignation is the loss of influence at the top table. However, given Blair's deafness, it probably won't make any difference in this instance.
There has been widespread anger and dismay in this country over the way Tony Blair has supported the US government in its illegal aggressive war in Iraq, his broken promises over the role of the UN in Iraq, and his connivance at US business interests taking over Iraq oil and construction projects. Perhaps Clare Short can provide a focus for the opposition within the Labour party to Tony Blair's betrayal of all the Labour Party stands for.
Tony Cheney, UK
It's a sad day, I think she was right to stay through the war and do as much as she could from a position of power. The fact she thinks it impossible to continue reflects the chaotic political and humanitarian situation that Blair and Bush have allowed to develop in a stubborn stand against the logical involvement of the UN. Maybe it's Blair who should consider his position in light of the broken promises he made to the country.
Tony has done fairly well. Now there's only Prescott (what's happened to him?) to go and he won't have a single left-winger left in the Cabinet.
Tony, Hammersmith, UK
She tried to do her best for the Iraqi people under the circumstances. But it shows as long as Blair is around there is no chance of that. I personally think she should have resigned before the illegal war as more people would have followed.
A. Rana, London, UK
I think she was right to stay on the eve of a war when our troops were going into battle. And I think she is right to go now that it has been proved that the reconstruction is little more than "jobs for boys" carve up by the US administration - not that it was ever likely to be anything else.
About time! Now, let's move on!
The charade is now over... but it raises important questions over Blair's assurances to the UK public over the war in Iraq. Does this mean we can look forward to Tony Blair resigning as well since he is now such a man of principle?
Phil King, UK
Clare's resignation is appropriate, it's fairly clear to the rest of us that Blair has failed to deliver on Iraq from the start to this moment. Contrary to the common view, I think that she was correct to stay before, to be in position to rebuild from the war that Bush and Blair were so obviously intent on, whether Clare stayed or not. The focus is back on Tony to deliver, some truth about Iraq would be a good start.
Barry B, UK
Short was an unacceptable loose cannon and has only jumped before she was pushed anyway.
Maurice Davies, UK
This government needs more loose cannons not less. The idea that everyone should toe the official line right or wrong is an insult to intelligent people and prevents a rational assessment of all possible courses of action. We need more people in the Labour party to think and act independently of government edict.
John Small, UK
She brought discredit to the left, to the right, and in fact to the whole country. I look forward to her appearing in next year's I'm A Celebrity, Get Me Out Of Here programme, as she has no credible future in British politics.
This is a sad but not unexpected outcome - however she should, of course, have resigned when the Iraq conflict began.
She would have gained more respect from everyone had she quit at the same time as Robin Cook.
Andy Bugden, UK
I feel sorry for Clare Short. She has resigned at the wrong time. Had see resigned before the war with Iraq her political integrity would be intact. Now her word is harder to take at face value and it will hurt her political future and be a sad loss to the country. Clare was a voice of reason and principle in a blinkered and ambitious cabinet.
Stephen Hoole, U.K
This has been two months late in coming. Had Short resigned back then she would have some credibility left - but her U-turn on the Iraq war finished her off as a political heavyweight.
I thought Tony Blair should have sacked her from day one, but actually, he's played a blinder. She's lost all credibility by staying when she said she'd go, and now she's gone anyway. No great loss.
Too little too late. She should have gone when she first threatened to resign, and kept her reputation intact.
Ewan MacKenzie, UK
It was inevitable; no one really believed Tony Blair would hold onto her once the war was over. I have no sympathy for her; I hope she spends some time reflecting on the severe damage she did to the anti-war movement when she put her career above her principles.
C. Booth, UK