The leader of Britain's opposition Liberal Democrats resigned under heavy pressure from the party on Saturday, days after he acknowledged battling a drinking problem.
Charles Kennedy initially resisted resigning despite calls from nearly half of the party's lawmakers for him to quit, saying the Liberal Democrats' rank and file still backed him.
He changed course on Saturday, saying he was resigning effective immediately and would not run in the leadership elections he announced on Thursday.
"In all of this, the interests of our party have got to come first, that's where my personal, my political and my constitutional duty lies," Kennedy said in a news conference at the Liberal Democrats' headquarters in central London.
He urged the party, Britain's third largest, to maintain its most important priorities: "Civil liberties, justice and the rule of international law, Britain again seen as a force for good in the world ... a far fairer social deal for the have-nots in our society," and greater concern for the environment.
Kennedy's deputy, Menzies Campbell, 64, took over as interim leader and quickly announced his intention to run in the leadership contest.
Popular and well-respected, he could emerge as a consensus candidate in a party eager to avoid further division.
Other likely candidates are party president Simon Hughes, 54, and domestic affairs spokesman Mark Oaten, 41.
With local authority elections due in May, the Liberal Democrats will be under pressure to choose a new leader quickly and get back on track. Kennedy said he would stay on in the House of Commons as a back bench lawmaker and promised to support his successor.
Kennedy's relaxed, amiable style and his opposition to the Iraq war had made him a popular and respected politician. The Liberal Democrats were the only one of the three main parties to oppose the war, which was deeply unpopular among Britons.
But dissatisfaction with Kennedy's leadership had been simmering for months and increased sharply after the Conservatives boosted their fortunes by electing a charismatic young leader last month.
Kennedy, 46, acknowledged for the first time on Thursday that he had sought medical help for his heavy drinking -- after a television network contacted him with detailed allegations -- and he called a leadership election in which he initially said he planned to run.
Many of the left-leaning party's 62 lawmakers expressed worry at the prospect of such a divisive contest and urged him to step down soon and bring the party's crisis to a quick resolution.
Some said his drinking had compromised his political skills and expressed anger at his years of denying that he had a problem.
Others felt his leadership had been weak and ineffectual, and that he lacked the charisma and drive to challenge Prime Minister Tony Blair.
Party colleagues said stepping down was the right move.
"Charles Kennedy has taken a courageous decision and the right one for himself and the party," said Paddy Ashdown, Kennedy's predecessor as leader.
Rumors about Kennedy's alcohol abuse had been widespread for years.
In 2004, he stunned many by failing at the last minute to appear in the House of Commons for one of the year's most important political events, Treasury chief Gordon Brown's budget presentation.
The party said Kennedy had taken ill, but many suspected he had been drinking.