Michael Howard has been urged to fight the next election from the centre ground of British politics.

The Conservative leader has been under fire following poor by-election results and a perceived failure to land major blows on the prime minister following the publication of the Butler report.

Commentators also criticised his recent announcement that he would not have voted for the specific parliamentary motion that  authorised the war if he had known then about the intelligence failings.

There was further bad news when a poll suggested the Tories were level pegging with the Liberal Democrats.

But former Conservative Cabinet minister Lord Heseltine said it would be a mistake to shift the party to the right in response to the difficulties.

Such a move would be a "suicide decision," he warned. "You win from the centre," Lord Heseltine told the BBC.

Meanwhile, Michael Portillo said Howard had "broken his own bat" by appearing to change his mind on the war.

"The Tories can win only on the centre ground," he added in an article for the Sunday Times.

But shadow family minister Theresa May backed the Tory leader.

"Michael Howard has given the party a new stability and purpose," she told BBC Radio 4's World This Weekend.

"He has re-energised the party and he has shown us that we can win again."