The Prime Minister’s chief of staff is expected to be interviewed under caution for a second time by police investigating the cash-for-honours affair. The Times has learnt that Jonathan Powell is likely to be questioned about an alleged cover-up which appears to have hidden evidence from the ten-month inquiry.

The disclosure will mean that Tony Blair’s most senior aide will be asked if he knows of an alleged plan to hide from detectives the nomination of Labour’s lenders for honours. It will also increase pressure on Mr Blair, who is facing calls from his backbenchers to step down.

But it is pressure that Mr Blair remains determined to resist. This morning, at his twice-yearly appearance before the Commons Liaison Committee, the Prime Minister will, if asked, set out a busy programme of action for the next few months and reinforce the impression that his departure is not imminent.

There is also huge doubt over what he would do if any of his aides were to be charged. Some Labour MPs think he would have to go. But friends think that unlikely, saying he would do nothing to prejudice the defence case of his aides. “A charge is not a conviction,” one said. “He will go in his own time.”

Mr Blair’s appearance before MPs comes as the most recent poll suggests that Labour has largely shrugged off the latest allegations.

The Populus poll for The Times was undertaken over the weekend after news that Mr Blair had been questioned again, and amid speculation about possible charges.

However, support for Labour has firmed to 33 per cent, up one point since early last month, while the Tories are three points down at 36 per cent, at the lower end of their recent range. The Liberal Democrats are on 19 per cent, up one point.

Whitehall sources said yesterday that the police’s renewed interest in Mr Powell comes as they investigate allegations of a conspiracy to cover up evidence. One said: “He is highly likely to face another grilling. He [Powell] attended meetings that have yet to be adequately explained. He may also be able to shed light on why certain documents disappeared.”

In particular, police will ask Mr Powell about a meeting he attended with Lord Levy, the chief fundraiser, Ruth Turner, No 10’s director of government relations, and John McTernan, director of political operations, early last summer after the first arrest in the investigation.

Detectives have told the Crown Prosecution Service (CPS) that they have received information that the meeting discussed how to “handle” the police inquiry, a source said.

It has been alleged that Lord Levy was questioned about a note of the meeting, said to have been held at Downing Street, when he was arrested last month for allegedly conspiring to pervert the course of justice. Mr Powell will also be asked if he has any knowledge of missing documents which appeared to have been hidden from the investigation. The police’s agenda switched in December from the issue of loans to one of a conspiracy to pervert the course of justice, as revealed in The Times.

According to a senior source, police believe that they now have evidence to recommend charges against three people and have sent files to the CPS.

Mr Powell, 50, Mr Blair’s close friend and confidant, was first interviewed by police last summer. He was then interviewed for the first time under caution last month. All those questioned and arrested have denied any wrongdoing.

The Populus poll suggests that the public is sharply divi-ded about whether it is in the national interest for Mr Blair to stand down immediately: 49 per cent agree, with 45 per cent disagreeing. Labour voters disagree, by 66 to 33 per cent. More than half the public (56 per cent) say that the loans- for-peerages allegations have “significantly reduced” their trust in the Labour Government. But as many as 43 per centsay that the police investigation seems “to have been unnecessarily heavy-handed.

Populus interviewed a random sample of 1,509 adults aged 18 plus by telephone between February 2 and 4. The results have been weighted to be representative of all adults. Full details are available at www.populuslimited.com

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