Kenneth Clarke has revealed that he still has ambitions to lead the Conservatives.

However, the former chancellor was keen to play down any talk of a challenge to Iain Duncan Smith.

Speaking to The House Magazine, Clarke said that "contrary to a widely-held belief I don't spend every working day planning to be leader".

However, the outspoken backbencher admitted that "I'd probably try again if the opportunity presented itself and I was still young enough."

But it is now unlikely that any leadership challenge will come from within the party before the next election.

Success in the May local elections and a narrowing poll gap between the Conservatives and Labour have bought Duncan Smith time as leader.

However, many critics argue that the self-styled "quiet man" of the Conservative Party has yet to make an impact on the public. And Clarke still feels he has what it takes to lead the Tories to success.

"My colleagues and I still have a lot of work to do to make ourselves look like a credible alternative government," he said.

"We have a potentially extremely unpopular government for which nothing is really going right at the moment, and so in mid-term we really should be far ahead in the opinion polls."

The implicit criticism of his party's leader may upset many Conservatives who are desperate to present a united front.

And many will feel that Clarke is too tarnished to be a credible alternative candidate.

As the chancellor outlines the reasons for Britain opting out of the euro, the pro-European stance of Clarke remains far from the rest of his party.

Speaking ahead of the announcement Clarke said "if we are not ready, we're very nearly ready".

"I don't think we should delay much longer," he said

"This issue has blighted British politics to a quite considerable extent for the last five or six years, producing indecision and delay, and leaving us a semi-detached member of the EU.

"I look forward to the day when we eventually get it over with," he added.

As well as his European stance, Clarke's decision to oppose the war in Iraq also set him apart from many of his parliamentary colleagues.

And it seems that despite remaining ambitious Clarke recognises that the best opportunity to grab the leadership has passed him by.

"I would have liked to be the leader of the Conservative Party and I still would," he said.

"But I've run twice and I can't see another opportunity coming up in the future."