Jamie Oliver, the television chef, celebrated a victory today in his campaign to raise the quality of food in British schools after the Government announced that it would pour an extra £280 million into school lunches over the next three years.

The announcement by Ruth Kelly, the Education Secretary, came less than two hours before Mr Oliver delivered a petition to No 10 Downing Street with 271,677 signatures collected via his Feed Me Better website.

Ms Kelly said that primary schools would now be required to spend at least 50p per pupil per day and secondary schools 60p per pupil per day - up from the current average of 37p. "It's the biggest sum that I've ever heard being put into school food and I think it will make a real transforming difference to school dinners," she said.

The decision was welcomed by Mr Oliver, who said after delivering the petition to Tony Blair:

"Instead of being the embarrassment of Europe, we could be celebrating England and its food in the next five years."

The Prime Minister added: "It's an idea whose time has come. It's obvious we should do it."

Opposition parties attacked the move as cynical electioneering, and the Conservatives said they would not just match the funding pledge but would ban junk food in schools - a move that the Government is still shying away from.

"After eight years in office, ten Education Bills, four secretaries of state and a five-year education plan last year which did not even mention the issue, it is breathtakingly cynical for Tony Blair suddenly to claim that he is passionate about the quality of school meals just because a celebrity chef has made a TV programme about it," said Tim Collins, the Shadow Education Secretary.

At a press conference this afternoon, Mr Oliver said he thought that the extra 13p spent on the average primary school meal would help raise standards. But he expressed disappointment that the Government had not taken the relatively simple decision to ban junk food, instead of introducing more complicated nutritional standards.

"It's a nanny state thing - they can't be seen to tell people what to do," he said. "Sometimes when you have a crisis, like school dinners are in, you need to be a bit more compulsory and say, sort this out."

The 29-year-old chef managed to make the quality of school meals a nationwide political issue through Jamie's School Dinners, a four-part series on Channel 4 in which he weaned children from a dozen schools in the London borough of Greenwich off a diet of burgers, chicken nuggets and chips to fresh food including real meat and vegetables.

One of the highlights of the series showed him feeding Charles Clarke, Ms Kelly's predecessor at Education, a reconstituted turkey patty - which Mr Clarke duly ate - to show him the junk served in Britain's schools since a cost-cutting drive started in the 1980s.

The series touched a nerve with parents and Mr Oliver's subsequent online petititon has spawned thousands of local petitions across the country, forcing school heads, governors and local education authorities onto the defensive about the quality of food served to pupils.

The extra funding appeared to cut little sway with teachers, who were distinctly unimpressed by the proposal that Ofsted, the school inspectorate, would be asked to police the standard of food.

In Brighton, delegates at the annual conference of the NASUWT teachers' union groaned and laughed when Stephen Twigg, the School Standards Minister, outlined the proposals.

Chris Keates, the union's general secretary, asked how inspectors would go about such an evaluation. "Presumably, what they do is simply try school meals and then wait until the

morning?" she said.

But David Hart, head of the National Association of Head Teachers, said: "I don't really care very much whose bandwagon the Government is jumping on as long as they jump."

This month, Ms Kelly promised that Labour would bring in minimum nutritional standards for all school meals and processed food such as sausages, cakes and burgers will have to meet tougher rules designed to cut their levels of salt, sugar and fat.

The success of his campaign seems likely to transform Mr Oliver - who is already an MBE - from celebrity to popular hero.

Born in Essex, Mr Oliver was brought up in a pub, where he first started to cook. A stint in France was followed by jobs at Antonio Carluccio's Neal Street Restaurant in Central London and the River Cafe - where his ease with the television camera was noticed by a visiting crew. His first television series, The Naked Chef, was filmed in 1998.

He has since made five more series - accompanied by best-selling books - and opened a restaurant in the East End where unemployed youngsters are trained as chefs. He enjoys growing international success and is a major television draw in the United States.

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