Speaking in Basildon, Essex, Mr Brown said: "I told the Shadow Cabinet today that a Labour government will spend more on the NHS. Indeed government spending will rise in real terms faster than inflation."
But he added that he and Chris Smith, the party's health spokesman, would be setting one condition for the extra money: "a condition that will bring comfort to every patient of the NHS. Yes, we will give the NHS more money every year. But unlike the Tories, we will insist that every penny of that goes not to administration, but to patient care."
One of Mr Brown's aides said later that the promise would be included in Labour's manifesto, finalised at a special meeting of the Shadow Cabinet and the party national executive yesterday, for publication next week.
"We're just showing that it is not true that the Tories are spending more on the NHS than we plan to," he said. "What is more important is our commitment to move funding from bureaucracy into patient care."
Earlier, Tony Blair had promised that the Labour manifesto would help create a bond of trust with the electorate, and would not promise anything that could not be delivered.
In spite of Conservative efforts to divert attention from the main themes, by concentrating their fire on trade union rights, Mr Blair played up the "number one priority" of education, saying: "A vote for Labour is a vote for small class sizes, better-quality teaching, new targets for reading and writing, more nursery places and a chance to learn new skills throughout your life."
David Blunkett, the party's education spokesman, said: "This will be the education election." But the Labour leader also said that the new manifesto would mark "the burial of tax-and-spend politics from Labour" and that it would contain an agenda for tax cuts.
"It pledges that we will cut VAT on heating to its lowest possible level of 5 per cent. And, for the first time, it includes our ambition to cut the starting rate of tax to 10p."
He said later, however, that the 10p starting rate of income tax was an "ambition" and not a firm commitment, with timescale attached. "We're not going to make promises that we can't deliver on this," he said.
Asked whether the burial of tax and spend and his agenda for lower taxes meant a cut in the overall tax burden, Mr Blair made no commitment either way - other than to say that while the Tories were promising reductions in Capital Gains Tax and Inheritance Tax for the benefit of the wealthy, Labour would concentrate its efforts on tax cuts for the low-paid. He said any pledge made "we will keep and the single most important thing in this election in relation to tax is going to be to rebuild the trust between government and people because that trust was broken by the Conservatives".
Today is the fifth anniversary of John Major's pledge, given during the 1992 election campaign, that there would be no extension of VAT. It was extended to domestic fuel and power bills in the 1993 Budget.Reuse content