Nick Clegg endured a torrid 24 hours in Brighton yesterday after being handbagged by Sir Menzies Campbell’s wife for admitting that he harboured leadership ambitions and after revealing that he had been sentenced to community service for a drunken student prank.

The Liberal Democrat Home Affairs spokesman was ambushed by Elspeth, Sir Menzies’s outspoken and fiercly loyal wife, in the foyer of the Grand Hotel after saying at a fringe meeting on Tuesday that he would probably stand for the leadership.

In the exchange, caught by ITV News, she remonstrated: “I don’t know if you’re being helpful or not.”

A slightly abashed Mr Clegg replied: “I’m trying to be.”

Sir Menzies sprang to his front-bencher’s defence, saying: “He’s being very helpful.”

Lady Campbell retorted: “It’s so difficult.”

The exchange came after Mr Clegg was asked about his ambitions at a fringe meeting on Tuesday night. Mr Clegg said: “If you are asking me would I stand against Ming, the answer is no.” When pushed on the issue, he responded: “If there was a vacancy in the future then I probably would.”

Despite a widespread expectation that Mr Clegg would stand when Sir Menzies retires, he has been cautious not to spell out his intentions so explicitly. Mr Clegg’s colleagues, including several of those likely to back him in any contest, were not impressed. One told The Times that the remark showed his relative inexperience in politics, having been elected to Parliament as recently as 2005. Another said that he should have replied with a different formula of words.

Mr Clegg’s remarks prompted an immediate response from Chris Huhne, the Environment spokesman and a likely fellow contender, to issue a barbed statement suggesting comparisons between Mr Clegg and Michael Heseltine, who failed to become Tory leader. He said: “There is no vacancy and this is premature to even talk about the possibility of there being a vacancy.

“I am not a sort of Michael Heseltine figure who plans the road map to Downing Street from the day they come out of nappies. I wait for opportunities and then decide at the time.

“I am very happy with what I am doing. I am very pleased Ming asked me to do the environment brief, which I think is the key challenge facing the country.”

Sir Menzies played down the controversy, reminding would-be leadership hopefuls that there was no vacancy. He added: “I like Young Turks. I was a Young Turk myself and that is why I have promoted Young Turks, male and female, into the Shadow Cabinet. I like ambition. I have been ambitious myself all my life. I am totally relaxed.”

He praised Mr Clegg and Mr Huhne as talented politicians, but he also issued a pointed reminder that they would not necessarily be the only contenders when the time came. “Remember, there are some women of talent around and some other men as well,” he said. “When the runners and riders are finally declared at some unspecified time in the future, then there will be plenty of talent to choose from.

“But let me make it very, very clear: there is no vacancy, I shall lead this party through this Parliament, through the general election, and into the Parliament beyond.”

Mr Clegg also admitted at a fringe meeting yesterday that as a 16-year-old exchange student in Munich he and a friend set fire to a valuable collection of rare cacti in a “drunken prank”. He was caught and sentenced to community service, digging up gardens. When he returned to England, he had to spend the holidays, and a lot of money, finding the cacti that he had destroyed and sending them to the professor whose collection he had ruined.

Today Sir Menzies will close the conference with a speech in which he will tackle the issue of the leadership head on, according to aides. He will also make a robust defence of Europe while outlining five freedoms that Liberal Democrats would defend.

“What our country needs is a political party that is prepared to take the lead and speak the truth,” he will say. “Because on so many of the major political issues there is a two-party consensus that we alone can break. That we must break.

“Only we can achieve that free, fair and green society. Because only we believe it. Only we will work for it. Only we will fight for it. The Liberal Democrats versus Labour and the Tories. Today, our party is not only the real alternative. It is the only alternative. Not two against one. But one against two.”

The protagonists

Nick Clegg, 40 Home Affairs spokesman Born in Buckinghamshire to a Dutch mother and half-Russian father. He is a former journalist and MEP who went to Westminster School and Cambridge University. Married, with two sons. Brought up bilingually in Dutch and English and also speaks Spanish, French and German. Used to work for Leon Brittan, the Conservative European Commissioner. Speaking at eight conference fringe events

Chris Huhne, 53 Environment spokesman Also a former journalist and MEP who went to Westminster School and Oxford University. Married with five children. Stood for election as party leader last year, coming second with 21,628 votes to Sir Menzies Campbell’s 23,264. Used to own a BMW 7 series car. He is speaking at 13 conference fringe events

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