Geoff Hoon, the Europe Minister, ignored the Prime Minister’s appeals for silence and suggested that he consider going before the Scottish Parliament and Welsh Assembly elections, where Labour faces a wipe-out.

In his first intervention since returning from a trip to Kazakhstan, which meant that he was away during last week’s wrangling over the Labour leadership, he said: “Having set the outer limits of how long he is staying, that still leaves questions in the context of the elections in May. A lot of people will be asking if it makes sense to him to carry on through those elections.”

This week The Times revealed that Mr Blair was considering plans to announce his resignation after the March Budget, then standing down in late May or early June. This would mean an eight to twelve-week leadership contest being held at the same time as campaigning with the Scottish and Welsh elections. Activists fear that this could distract from campaigning and deepen their polling woes.

Mr Hoon, who is close to Gordon Brown but hitherto publicly loyal to the Prime Minister, is the first minister publicly to call for Mr Blair to break ranks and go before the elections. He was left feeling bitter after Mr Blair demoted from Leader of the Commons to a Foreign Office position under Margaret Beckett.

Nevertheless he insisted yesterday in an interview with the Evening Standard that he was still loyal and that Labour activists wanted Mr Blair to quit “on a high”. Mr Hoon’s surprise intervention will increase pressure on Mr Blair to name an exact date for his departure.

Endorsing the Chancellor as Mr Blair’s successor, he added: “I think Gordon should be the next leader so we should think very carefully about who we want to be in place when we face our next poll test.”

Meanwhile, the former Blairite minister John Denham attacked the Government as over-centralised, narrowly focused and policy-deficient. In an interview for The Sunday Programme on GMTV, he argued that the Government had lost its focus.

“At one level we only talk about small parts of people’s lives. Reforming public services and dealing with antisocial behaviour are both important but they don’t amount to a vision of a new society. We have lost that.

“Secondly, there are areas where clearly, despite our opportunities, we have not done as well as we might have done. We backed away from challenging big vested interests: look how long it has been taking us to deal with school dinners or the powerful forces that are promoting obesity.”

Mr Denham continued: “Our Government has become too centralised, so much is funnelled through the narrow channel at Downing Street that we have become slower in responding to new policies. Some of our new policies haven’t been well designed.”

Mr Denham, who resigned as a Home Office minister over the Iraq war, added: “I think we have explored the limit of how much social change you can achieve by driving everything from the centre. What is quite clear to me at the moment is that a number of major government departments are not operating on all cylinders because effectively they are looking all the time to see whether they will have approval from the centre.”

Times Recommends

• Third of Muslim students back killings
• Curfew tames feral yobs of Cornwall
• £3,000-a-month drug free abroad