Frustrated at his inability to escape the row that has now rumbled for five days and knocked his party’s campaign off course, Mr Blair warns the Conservatives that their character assassination will not work because of the decency and good manners of the public.

But the Prime Minister will run into a new cronyism row today as The Times discloses that he is about to create 16 Labour peers, making his party the largest group in the Lords for the first time in history. Labour will have 218 peers.

The dissolution honours list, to be published tomorrow, creates five Tory peers, taking Michael Howard’s group in the Lords to 208. The Liberal Democrats will get five peers.

The list will provoke controversy with peerages for Dennis Turner, who stood down at the election to make way for one of Mr Blair’s advisers, Lewis Moonie, who gave up his constituency when Gordon Brown’s disappeared through boundary changes, and Alan Howarth, the former Tory MP who boosted Mr Blair’s standing in 1995 by joining Labour.

Meanwhile it has emerged that thousands of voters could be disenfranchised in the general election next week because of printing and human errors involving postal ballot papers.

Ballot papers sent out from at least three constituencies could be void because of a mismatch of identification numbers in the ballot pack.

All three constituencies, which have not been named, could face legal challenges if the results are close or from individuals unable to vote.

Exasperated at the continued battering he is receiving over Iraq, Mr Blair will today try to open a new front with his strongest offensive on the Lib Dems’ economic policies.

Charles Kennedy emerged as the surprise winner of last night’s interrogation of the three party leaders in a BBC Question Time special. The Liberal Democrat leader’s serious and businesslike manner appeared to win over the studio audience, while Mr Howard lost credibility when he had to concede that he would have backed the invasion of Iraq even if he had known that no weapons of mass destruction would be found.

Mr Blair rounded off a difficult day without any major slips, although commentators felt that he lacked some of his usual vigour and composure.

But after a day in which the Chancellor rode to Mr Blair’s rescue by strongly endorsing his handling of Iraq, Mr Blair reciprocates, in an interview in The Times, with the warmest backing for the man expected to be his successor.

Insisting that he is trying to avoid headlines suggesting who the next prime minister will be, Mr Blair suggests that he has said on many occasions that “Gordon will make an excellent prime minister”.

He talks of the fantastic way that they have worked together in the election and how there has been a “strong coming together” over public service reform. Their relationship, he says, has been the “foundation of the Government”. He adds that “new Labour will not be undone”. But Mr Blair admits his exasperation at how Iraq has hijacked his campaign in recent days and claims that he has “busted a gut” to get proper discussion of policies.

He says that all he has heard is a “stream of abuse” from the Conservatives, whom he accuses of avoiding difficult policy questions and concentrating on immigration and attacks on him. “It is a very small-minded campaign and I do not think it works. British people in the end are well-mannered and decent and what they will look for is a big set of policy ideas,” he said.

However, the Prime Minister bowed to the inevitable and published in full the legal advice on the war from Lord Goldsmith, the Attorney-General.

He said that the smoking gun promised by the leaks was a damp squib, because the document showed that Lord Goldsmith did consider that the war was lawful.

Mr Blair came under fierce attack from opponents. Mr Howard said that the overnight leaks were devastating and proved that Mr Blair had lied. The Tory leader said: “The issue of Iraq boils down to one very simple question: if you cannot trust Mr Blair on the decision to take the country to war, the most important decision that any prime minister can take, how can you trust Mr Blair on anything else, ever again?” Mr Kennedy said that Mr Blair’s description of the advice as a damp squib showed that he was out of touch.

Earlier, Mr Brown, who had said little about the internal Cabinet debate on Iraq, had eased Mr Blair’s position.

Asked at a press conference with Mr Blair if he would have proceeded in the same way as the Prime Minister, he replied simply “yes”. “I not only trust Tony Blair but I respect Tony Blair for the way he went about that decision,” he said.

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