Sir Menzies Campbell has insisted that his age will be an asset at the next general election, as he attempts to calm Liberal Democrat jitters after a difficult week. Sir Menzies, 66, tried to defuse concerns over his leadership with an attack on the Conservatives for “colluding” with the Government and tackled head-on the criticism that he was too old to lead the party.

Speaking to staff at the Liberal Democrats’ headquarters in Westminster, he said: “Will my age be an issue? Absolutely. Because I will make it an issue. Politics would benefit from more people with experience.

“If more experienced politicians had taken the decisions, we might not be mired in the conflict that we see in Iraq today.”

The Liberal Democrat leader insisted that his was the only real opposition party and dismissed suggestions that he was ready to take jobs in a Gordon Brown government.

The speech follows the disclosure that Sir Menzies held talks with Mr Brown at which the incoming Prime Minister offered ministerial positions for senior Lib Dems.

Sir Menzies refused the offer and has been at pains to empha-sise his party’s distance from the Brown regime. Sir Menzies said that the Conservatives were in a “cosy consensus” with Labour on issues such as nuclear power and the war in Iraq.

“We have consistently opposed the centralising and authoritarian tendencies of this Labour Government,” he said. “I am not prepared to trade our principled opposition for the sake of ministerial jobs.”

He also went on to accuse Mr Brown of sharing responsibility for growing inequality and the war. “We will be there to remind everyone that his fingerprints are all over the scene of the crime,” he said.

“The lead actor may have changed but the plot is just the same. Never has there been a chancellor who has exerted so much influence over domestic policy. So it’s no good saying that we are starting afresh. The record of the last ten years is the record of Gordon Brown.

“Under a Brown premiership, the Liberal Democrats will rattle the cage of British politics,” he added.

“We will expose the Government on BAE, freedom of information and the erosion of civil liberties. We will give a political voice to those who are not being heard in government.”

Sir Menzies will seek to keep alive cross-party talks on issues such as climate change and constitutional reform, but insists that there is no chance of the Lib Dems joining a Labour government.

There are fundamental differences over nuclear energy, identity cards, the war in Iraq and city academies, he said.

“On these issues and so many others, we are the only party of true opposition because the Conservatives are in collusion with the Government on all of them.”

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