Blair in show of unity with Levy amid rumours of rift

The Metropolitan Police has announced that John Yates, the police officer leading the "cash for peerages" criminal investigation, has been promoted.

The current deputy assistant commissioner is being promoted to become the Metropolitan Police's fifth assistant commissioner on a starting salary of £163,908, more than a cabinet minister. It is the third highest post in Britain's largest police force.

His promotion will infuriate some Labour MPs, who have privately accused him of "going over the top" during an inquiry that has led to the humiliation of Mr Blair by making him the first serving prime minister to have been questioned by police in a criminal investigation.

Meanwhile, during a press conference in Jerusalem yesterday, Mr Blair praised the "excellent" work done for him in the Middle East by Lord Levy, the Labour chief fundraiser. The mention was seen as a show of unity after a recent "war", when both men seemed to blame each other over the cash for peerages row.

"He [Lord Levy] has performed an excellent job as my envoy in very difficult circumstances, when we desperately have to make progress." Mr Blair added that Lord Levy had been "immensely helpful to me" in laying the ground for his attempts to revive the Middle East road map to peace.

It also emerged last night that Mr Yates has warned MPs in private that he will force Downing Street to release records, if necessary.

It follows reports that Met investigators have found some of the Downing Street e-mails in the "paper trail" of evidence at the heart of the investigation have gone missing. It led to claims that No 10 officials could face a separate inquiry for perverting the course of justice.

Downing Street denied withholding documents yesterday. "The Prime Minister has made it clear consistently that Downing Street will co-operate with the police and the police should have access to all the relevant material. That has been the position throughout," the Prime Minister's official spokesman said. But Mr Yates told MPs on the Commons Select Committee on Administration, which is investigating the honours system and which has so far not reported, that there were "gaps" in the evidence provided by the parties, including the Government, and that he would act, if necessary, to gain the missing information.

"It has taken some time to gather what they consider to be relevant and provide it to us. There are some gaps in the information," he said. "It would, of course, be regrettable from our perspective if we had to resort to any more formal means to gather this material."

Jonathan Powell, the Prime Minister's chief of staff, and Ruth Turner, the director of government relations, will be questioned for a second time.

Mr Blair's denials over any wrongdoing during his police interviews put the pressure back on Lord Levy, who is facing a third interview with police. There were claims there was a "war" between the two men after Lord Levy's friends appeared to put the blame back on the Prime Minister, saying he had sole responsibility for peerages.

Lord Levy's friends deny knowledge of a note reportedly written by Sir Christopher Evans, a biotech millionaire who gave Labour a £1m loan, saying "Wd you like a K or a big P?" in reference to an inquiry about a knighthood or a peerage allegedly made by Lord Levy. He is said to be ready to answer police questions after Christmas. "Michael is worried but still bullish about it," said one friend of the Labour peer.

Lord Levy gave evidence to a Select Committee on Constitutional Affairs chaired by Alan Beith, the Liberal Democrat MP, who will deliver his report today.