Ex-Cabinet minister Clare Short was asked about the decision to drop charges against sacked GCHQ translator Katharine Gun.
Clare Short has been a thorn in the government's side since she quit
Mrs Gun admitted leaking a memo apparently requesting UK help in bugging UN officials in the run-up to the Iraq war.
What follows is a full transcript of the interview on Radio 4's Today.
Presenter John Humphrys asked Ms Short why she thought the prosecution decided it lacked evidence for a prosecution.
Clare Short: Well I think this centres on the attorney-general's advice that war was legal under Resolution 1441, which was published as a matter of fact, but was very, very odd.
The more I think about it the more fishy I feel it was. It came very, very late.
He came to the Cabinet the day Robin Cook resigned and sat in Robin's seat. Two sides of A4, no discussion permitted. We know already that the Foreign Office legal advisers had disagreed and one of them had said there was no authority for war.
The Liberals have been pressing for the brief on the basis of which he said there was authority for war.
There's a question of whether the exaggeration of the threat and the immediacy of the threat from any possible biological and chemical weapons in Iraq was part of the brief for the attorney-general so that he would give the legal authority.
So my own suspicion is that the attorney has stopped this prosecution because part of her defence was to question legality and that would have brought his advice into the public domain again and there was something fishy about the way in which he said war was legal.
Q: What this memo showed - the secret memo that Katharine Gunn disclosed - what it showed was pressure by the United States on other countries to get support for a second united resolution and spying indeed on those countries.
Do you believe that Britain - that our government - might have been involved in that with the United States?
CS: Well there was enormous for [inaudible] a second resolution and then of course it is clear now there was a date for war so they didn't need Blix to do his job and then come to a second resolution if need be.
But they were going to war anyway and they were going to bully and pressure countries to vote for it.
I mean enormous pressure was brought to bear - Valerie Amos, Lady Amos, went round Africa with people from our intelligence services trying to press them. I had to make sure that we didn't promise a misuse of aid in a way that would be illegal.
Q: A view - was it being suggested then?
CS: There was worry about her brief and making sure that there was no such suggestion because it would have been a breach of the law...
Q: But can I question you on that for a second - did somebody suggest that that might have been the right strategy?
CS: We were worried that that was going to be done and went to some trouble to make sure her briefing made it clear that that could not legally be done.
I mean the UK in this time was also getting - spying on Kofi Annan's office and getting reports from him about what was going on.
The US was pressing Chile, Mexico - enormous pressures were brought to bear. What's remarkable is that these countries didn't break.
And if you remember the other part of the context is we were then all deceived about the French position and told the French had said they'd veto any second resolution - which wasn't true, we now know.
Chirac said we'd veto now because Blix needs his time but if Blix failed then of course we would vote with others to organise military action.
Q: But pressure is one thing - you expect that I suppose, spinning is another thing, you expect that I suppose.
Spying is something quite different - spying in the United Nations is something quite different isn't it?
CS: Well indeed. But these things are done and in the case of Kofi's office it's been done for some time.
Q: Indeed again, let me repeat the question then - do you believe Britain's been involved in it?
CS: Well I know - I've seen transcripts of Kofi Annan's conversations.
In fact I've had conversations with Kofi in the run up to war, thinking 'oh dear there will be a transcript of this and people will see what he and I are saying'.
Q: So in other words, British spies - let's be very clear about this in case I'm misunderstanding you - British spies have been instructed to carry out operations within the United Nations on people like Kofi Annan?
CS: Yes absolutely.
Q: Did you know about this when you were in government?
CS: Absolutely, I read some of the transcripts of the accounts of his conversations.
Q: Is this legal?
CS: I don't know - I presume so. It's odd but I don't know about the legalities.
But the major issue here is the legal authority for war and whether the attorney-general had to be persuaded, at the last minute, against the advice of one of the Foreign Office legal advisers, who then resigned, that he could give authority for war and whether there had to be an exaggeration of the threat of the use of chemical and biological weapons to persuade him that there was legal authority - that's the big question.
Q: And what should happen now?
CS: I think the good old British democracy should keep scrutinising and pressing to get the truth out.
Q: How? There's been a lot of it and a lot of people now are beginning to say and indeed have already said - well look we've heard it all, we've had the war, it's all over, let's put it behind us.
Tony Blair certainly wants to put it behind us.
CS: Yes but the tragedy is Iraq is a disastrous mess; 10,000 Iraqis have died, American troops are dying, some of our troops have died.
The Middle East is more angry than ever. I'm afraid that the sort of deceit on the route to war was linked to the lack of preparation for afterwards and the chaos and suffering that continuous - so it won't go away will it?