Gordon Brown is to promise patients cancer tests within one week of referral as he puts the defence of frontline services and the economy at the heart of his party’s — and his own — survival plan.

The Prime Minister will pledge to divert £1 billion over five years from building new hospitals to buying diagnostic treatments that will guarantee a patient’s right to a test and results within seven days. Anyone who does not get the test and results in seven days would be entitled to go to a private provider free. The scheme will save 10,000 lives year, Labour advisers claim.

It will be one of several announcements in Mr Brown’s speech to the Labour Party conference next Tuesday designed to show voters that they will have a “big choice” election next May with sharply different offerings from Labour and the Conservatives on the economy and public services. It will form the centrepiece of a speech that Mr Brown accepts must reverse the startling drain in confidence in him within the Labour party in recent weeks, exacerbated by the rows over the Lockerbie bomber and the Attorney-General’s housekeeper.

Mr Brown has been convinced by strategists such as Lord Mandelson that he must show that Labour will change the country just as much as the Conservatives claim that they will.

But he is also reported to know that he must address the doubts about his leadership and accept that he has flaws and that there are things about him that the public does not like.

As Cabinet ministers talk privately about Mr Brown’s future, close friends say that he is showing not “one scintilla” of doubt about his determination to carry on.

They say that he is aware of the murmurings but that he will address them head on as he enters conference week, making plain that he has no intention of walking away.

Senior ministers told The Times this week that the only scenario in which there could be change without a damaging internal election would be if Mr Brown voluntarily gave up — which is not in his mind — and if there was agreement about a stopgap successor — which there is not.

Jack Straw and Alistair Darling are felt to have ruled themselves out for that role and Alan Johnson, who was seen as a possible figure to emerge from the shadows in the summer, is felt to have reduced his chances by not moving at the time. In union circles, however, the idea of Mr Johnson surfacing as an agreed candidate shortly before the election is still being canvassed.

Any of the younger candidates would almost certainly not be given a clear run.

Mr Brown regards his Tuesday speech as the start, and most essential part, of a fightback that will go on for seven months.

He has called in all of his old allies such as Lord Mandelson, Ed Balls and Ed Miliband as he tries to shape a speech that will be as much about him as his policy agenda.

Mr Brown cleared his diary for three hours on Wednesday to run through his speech with the veteran US political consultant Bob Shrum, The Times has learnt.

The consultant, whose help in crafting Mr Brown’s first speech as party leader led to accusations that he had borrowed heavily from those of US presidents, was summoned to Mr Brown’s suite in the Waldorf Astoria in New York after Colonel Muammar Gaddafi’s 94-minute rant at the UN General Assembly pushed his own address back.

Allies of Mr Brown insist that Mr Shrum is only one of “large number” of trusted figures whom the Prime Minister has asked for help. “Some, like Bob, are old friends stretching back years,” said one.

Mr Brown continued to work on the speech late into Thursday night after he travelled to the Pittsburgh G20 summit and was expected to continue drafting on the flight back to London.

Mr Brown’s pledge on cancer tests will be part of an attempt to wrest back the initiative on health.

He will say that the plan, which will initially create a two-week right before bringing this down to a one-week right within five years, is in line with Labour’s approach of creating clear, enforceable rights across the NHS and the public services to underpin its offer of greater user control.

He will say that this stands in stark contrast to the approach taken by the Tories, who have said that they will abolish such rights or targets.

In the scrutiny of the election campaign, Labour strategists believe that the more patient-focused approach of real enforceable rights to care will contrast very favourably with the approach adopted by the Tories of no minimum standards, guarantees or rights.

Once the cancer test programme is implemented the NHS should have the capacity to deliver an additional 621,000 more ultrasound tests, 313,000 more CT scans and 188,000 more MRI scans a year.

The five-year plan to transform the diagnostic capacity of the NHS will be the centrepiece of the NHS prevention and early intervention strategy to be published in the autumn.

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