KENNETH CLARKE threw down the gauntlet to the Conservatives yesterday, challenging them to pick him as the one leader who could return the party to power - and launching a thinly-veiled attack on William Hague.

He became the fifth candidate to enter the contest and gave a typically robust performance in which he claimed that he alone could win back the millions of votes lost to Labour and the Liberal Democrats since 1992.

The former chancellor immediately sought to tackle head-on the thorny issue of Europe, insisting that he could lead what he acknowledged was a predominantly euro-sceptic party.

But while he said the two wings of the party had to come together, he showed little sign that he was prepared to compromise on his own strongly-held pro-European views, saying: "I remain a conviction politician."

While all Conservatives - including members of the shadow cabinet - would be allowed to speak out on the single currency, he made clear that they would have to tone down their language and not indulge in personal attacks.

Mr Clarke launched a scathing attack on the fiercely euro-sceptic approach adopted by the party under William Hague's leadership.

He said: "Throughout the last Parliament we used vivid language about the imagined threat to create a super-state and the mythical imminent risk of being governed from Brussels instead of Westminster.

"The electorate interpreted this as extreme English nationalism.

Although Mr Clarke did not attack the Richmond MP directly, he could hardly have been more scathing about his leadership record.

He called for an end to "opportunism and populism" - two charges frequently levelled at Mr Hague by Labour- and said the party should have done much better at the last election.