LONDON — America requested changes to a Group of Eight declaration on climate change that eliminate some targets for reducing greenhouse gases and delete language stressing the need for urgent action.

The proposed revisions are in a draft copy of the statement obtained by Bloomberg News. The document, dated last month, includes portions that the U.S. has requested be crossed out when a final version is released at the end of the G–8 summit scheduled for June 6–8 in Heiligendamm, Germany.

The items the U.S. wants deleted are limits on global warming to 2 degrees Celsius, targets for a reduction of greenhouse gases to half of 1990 levels by 2050, and language that says tackling climate change is an “imperative not a choice.”

“The U.S. is happy to sign onto endless pages of meaningless verbiage, but they refuse consistently to commit to measurable action,” said Philip Clapp, president of the U.S. National Environmental Trust, in a telephone interview from Washington. “These changes threaten a major breakdown in U.S.-E.U. relations. Global warming has risen to the top of the agenda for European governments.”

The European Union has made limiting warming to below 2 degrees Celsius one of its main environmental targets, with steep cuts in greenhouse gas emissions required to achieve it. The U.S. has requested the removal from the draft of a paragraph that states a temperature increase of more than 2 degrees Celsius from before industrialization will result in “largely unmanageable” risks.

One passage that is crossed out in the draft states: “Climate change is speeding up and will seriously damage our common natural environment and severely weaken global economy with implications for international security. We underline that tackling climate change is an imperative not a choice. We firmly agree that resolute and concerted international action is urgently needed.”

Another edit proposed by the U.S. is the removal from the document of a statement that greenhouse gas emissions need to peak within the next 10 to 15 years, followed by reductions of 50% from 1990 levels by 2050. The Bush administration has rejected the Kyoto Protocol, the only international treaty that sets specific targets for emissions reductions.

The protocol binds 35 nations and the European Union to cut emissions by 5.2% from 1990 levels by 2012. No targets have yet been set for a successor agreement after 2012, though governments are due to meet at a U.N. conference in December in Indonesia to discuss actions to fight global warming.

The draft document calls for “a clear message on the further development of the international regime to combat climate change” to be delivered at the U.N. conference, another passage the U.S. wants deleted.

The United Nations Intergovernmental Panel on Climate Change this year issued a series of reports that say global warming is caused largely by human activities, such as the release of greenhouse gases from burning fossil fuels. The panel has also outlined the expected impacts of rising temperatures, such as droughts and floods, and detailed ways to tackle the problem.

All of the panel’s reports were approved by governments, including the U.S.

The Bush administration said it didn’t comment on ongoing, private negotiations.

” We will let the leaders announce what they are going to announce,” said Kristen Hellmer, a spokeswoman for the White House Council on Environmental Quality. “There certainly is consensus that the Earth is warming, and we are working with G–8 partners and developing countries to address this.”

The annotated draft also indicates the U.S. has requested other numerical targets be removed from the statement, including ambitions to increase energy efficiency in the transport sector by 20% by 2020, and raise the share of alternative fuels used in transportation to 15% by 2020.

The requested changes pose a challenge for European leaders such as Prime Minister Blair of Britain and Germany’s Chancellor Merkel, said Mr. Clapp, the National Environmental rust president.

“Are they going to once more water down a text and allow the Bush administration something it can sign onto, and present it as if something has been accomplished, or are they simply going to say, ‘I’m sorry, we have completely different views about this, and we will not sign an ineffective document,”‘ he said.