Lib Dem leader Charles Kennedy has resigned, after pressure from senior MPs following his admission of a drink problem.
Lib Dem MPs, other politicians, friends and family have been giving their reactions.
SIR MENZIES CAMPBELL, DEPUTY LEADER AND FOREIGN AFFAIRS SPOKESMAN, NOW ACTING LEADER
Under his leadership the party has advanced to its best position
for 80 years and the party will forever be in his debt.
Today we must wish him and his family well.
As deputy leader I will be assuming his responsibilities with immediate
effect, and over the next 48 hours will obviously be consulting colleagues - but
I can confirm today that I intend to be candidate in the leadership contest
that is to follow.
SIMON HUGHES, PARTY PRESIDENT
For me and for the party it is a sad day - a very sad day indeed.
I speak as party president on behalf of the whole party to say there will be very, very many sad members and supporters today - because the end of Charles's leadership is the end of a hugely successful period for us as a party.
I have asked for people to be generous in accepting that difficult moments sometimes produce inappropriate reactions.
I hope now we will come together, in the short term under Menzies's leadership, in his interim position, which he will assume immediately.
And then under the new leader whoever that is when they are elected.
Today is a thank you day to Charles and Sarah and a sad day
for us - but it is a day that will let liberalism move on.
The job of the party now is to provide the rules and timetable for the
There are certainly many people who feel [Mr Kennedy] has been badly
That is a perfectly understandable point of view and I support it.
SARAH GURLING, KENNEDY'S WIFE
I am very proud of him - both personally and for what he has achieved for the party.
NORMAN BAKER, LIB DEM ENVIRONMENT SPOKESMAN
It is obviously a
sad day for Charles in particular, and for the party at large.
It is inevitable
that Charles had to go given the circumstances - but it does not take away from
him his immense contribution over the last six years.
His last speech was one of his best and the irony is if he had been
turning in that sort of performance day in day out we would not be where we are
LEMBIT OPIK, NI SPOKESMAN
He was the right man to do the job and
he has been hounded out by people who did not appreciate his qualities.
I am really sad that Charles Kennedy has gone.
The last few weeks you have seen me say quite sincerely he was the best man to carry on leading the party.
Unfortunately some fellow parliamentarians felt it was in their gift to force him out without an all-member ballot.
Well, they have got what they wanted, and we lose the most successful party leader we have had for 83 years.
It has been divisive, and I have got some very strong words to say which I will now share quietly and privately, about the performance of some of my colleagues.
They have violated the values of some of the party, and crucially they have given the impression their words and their views are more important than the electorate which chose him in the first place.
And that, I do not think, was very constitutional.
MARK OATEN, HOME AFFAIRS SPOKESMAN
It was incredible - given all the strain that Charles has been under, to make that kind of statement was marvellous.
He showed incredible dignity and he has also shown why he has been such a superb leader for the party.
It is a really sad day for the party, and I am upset.
After all the pressure that
Charles has had, that was a dignified, statesmanlike performance.
What I want to do is find
the best way forward to unite this party.
I need to speak to Menzies and Simon and other contenders, and see if we cannot
decide how best to move this party forward.
It is not a time for individual
ambitions - we need to reunite this party.
What the members are looking for now is for this party to
unite and come together - not necessarily a bloody leadership election campaign.
We need to talk through over the next 24 hours and find the most
sensible way of doing this.
That is what the activists deserve and it is what
Charles deserves as well.
It is now important that everybody unites around some way or other to get
this party back on track.
ALEX SALMOND, SNP LEADER
Charles Kennedy confronted
his problems and appealed for support - but his MPs have responded by knifing him
in the front.
Julius Caesar was better treated by Brutus than Charles Kennedy by
Charles Kennedy's departure is as much about ideology as lifestyle.
Scottish Liberal Democrats will feel angry at the treatment of Charles
Kennedy and rightly worried at the attempts to move their party on to Tory
NICOL STEPHEN, SCOTTISH LIB DEM LEADER AND DEPUTY FIRST MINISTER OF SCOTLAND
I am very sad that Charles Kennedy's leadership has ended in this way.
As everyone knows, I have always strongly supported him and his statement today reminded us of why he was elected leader.
This has clearly been a very difficult time for Charles and those close to him - but, as is typical of the man, he has decided to put the interests of the party first.
There is no doubt in my mind Charles Kennedy was the key reason why the Liberal Democrats did so well in the last two general elections.
In Scotland last May the Liberal Democrats had our best results in decades, coming second in share of the popular vote as well as in the number of seats won.
ED DAVEY, LIB DEM EDUCATION SPOKESMAN
The party will be very grateful for Charles primarily for the leadership he has shown in the party and for the successes he has achieved for the party - but also today for the very dignified and courageous decision he has taken having listened not just to Parliamentary colleagues but to the wider party...
A successor will be able to build on the success that Charles achieved.
I certainly hope
Sir Menzies Campbell will put his name forward.
He has a huge
amount of support, not just in the parliamentary party, but across the whole
We have a very strong message in the Liberal Democrats, a message
for a fairer society, a more liberal society, and Sir Menzies Campbell
would be able to build on the success that Charles has brought us to.
CHRIS DAVIES, LEADER OF LIB DEM MEPs
Charles's statement summarises the situation.
It was sad, but it was necessary because the alternative, as one colleague said to me about an hour and a half ago, was meltdown - weeks and weeks of division and an open goal left for our political opponents.
That simply could not be tolerated.
We had to deal with the situation quickly.
MATTHEW TAYLOR, LIB DEM MP
Whilst in many ways he will be sad at this moment, it is the right thing for him.
There will actually be some relief, as well as sadness now.
It is certainly right for the party, and we will now have to reflect on the leadership.
There will be a lot of people wanting to pay tribute to Charles - not just for his leadership, but the way he's handled it today.
LORD ASHDOWN, MR KENNEDY'S PREDECESSOR
Charles Kennedy has taken a courageous decision and the right one for
himself and the party.
The Liberal Democrats owe him a great debt as the leader who presided over
the highest number of seats and greater share of the popular vote for Britain's
third party in living memory.
Charles Kennedy is a man of high and varied talents, which I hope and believe
will continue to be put into the service of Britain and the party he led with
BEN RAMM, EDITOR, LIBERAL MAGAZINE
There was a lot of tension that had built up, a lot of frustration, particularly over the last five months after the general election.
And many of the young and dynamic figures certainly put their names to that petition (urging Mr Kennedy to go), now hopefully (they) will have the energy and the focus to move forward and we hope, have a wide-ranging, open and thorough debate about the party's future.
ANDREW GEORGE, LIB DEM DEVELOPMENT SPOKESMAN
Charles came to, in my view, the right decision.
The manner in which he made his statement really demonstrated really the quality of his leadership.
It is a very sad day. This is Charles's day.
It Is one on which we can reflect on the successes of his leadership over the last six years.
He has been a tremendous leader.
I am tremendously fond of Charles,,, but came to the conclusion that really given, in my view, in some cases the mendacious private briefings that have been going on behind his back and other activities that frankly his position really became unsustainable.
And so in the end this is a very, very sad day indeed but also one in which we can reflect on the great success that Charles Kennedy brought the party.