Correction Appended

LONDON, Feb. 24— Prime Minister Tony Blair laid out ambitious plans today to fight global warming by cutting carbon dioxide emissions in Britain by 60 percent in the next five decades and gently criticized President Bush for failing to do more to combat the damaging effects of greenhouse gases.

Framing the issue of global warming as one of national security, Mr. Blair said the United States was wrong to back out of the Kyoto Protocol of 1997, which sought to minimize noxious carbon dioxide fumes. The Bush administration drew the ire of a number of industrialized nations when it backed out of the treaty, arguing that compliance would cost American businesses too much money.

But today, in clear disagreement with Britain's foreign policy ally, Mr. Blair said economic growth and environmental awareness can coexist.

''Even the Kyoto targets have proved controversial with some countries, notably America,'' Mr. Blair said at a conference on sustainable development here. ''Many see it as a threat to the pursuit of economic growth. I believe this needn't be the case. If we harness new technology, the evidence is mounting that we can achieve a target of 60 percent, and at reasonable cost.''

The prime minister added, ''There will be no genuine security if the planet is ravaged by climate change.''

Mr. Blair's proposals on global warming would far exceed the standards of the Kyoto treaty, which would require countries to slash greenhouse gas emissions to below 1990 levels by 2012. That would amount to a 2 percent cut, Mr. Blair said. In his plan, Britain would cut the carbon dioxide it releases into the atmosphere by 60 percent by 2050.

Carbon emissions, the noxious fumes produced by cars and factories, have been cited as causes for global warming. The gradual warming of the earth's temperatures has unleashed catastrophic floods and storms around the world, causing enormous, irreparable damage, Mr. Blair said.

He said he and the Swedish prime minister, Goeran Persson, had written to Prime Minister Costas Simitis of Greece, whose country holds the rotating European Union presidency, calling on other European countries to adopt the 60 percent goal.

''Whilst Kyoto was an enormous achievement, it is simply not enough,'' Mr. Blair told the audience.

The government also promised hundreds of millions of dollars to make Britain more energy efficient and to spur the use of renewable power sources like wind and waves. It also plans to create an exchange system by 2005, similar to one in the United States, that will allow companies that produce too much carbon dioxide to buy credits from companies that fall below the threshold.

The plan, laid out in a white paper, steps away from any increase in the use of nuclear power to offset Britain's oil consumption -- a contentious issue -- but it does not rule out the construction of more nuclear plants.

Environmentalists praised Mr. Blair's plans today and said they hoped he would not stray from his goals of conserving energy and reducing greenhouse gases.

Britain, which produces oil and natural gas from fields in the North and Irish seas, will become a net importer of gas by about 2006 and oil by 2010 as its supplies dwindle, the white paper stated.

Mr. Blair said he would continue to press the United States and other industrialized countries to intensify their efforts to fight global warming.

President Bush sparked a furor among the signers of the Kyoto Protocol when his administration announced that it would not ratify the agreement, which it saw as unworkable for American companies. Instead, the administration sought voluntary commitments from companies to reduce carbon dioxide emissions.

''We will continue to make the case to the U.S. and to others that climate change is a serious threat that we must address together as an international community,'' he said. ''We in Britain have shown that it is possible to break the relationship between economic growth and ever rising pollution.''