Dec. 10 (Bloomberg) -- The Bush administration, which has long rejected mandatory limits on global warming pollution, opposes a United Nations draft proposal calling on developed countries to make binding emissions cuts of 25-40 percent by 2020.

``Our principal difficulty with having any numbers in the text to begin with is that it might prejudge outcomes,'' senior U.S. climate negotiator Harlan Watson said today at a news conference on the Indonesian island of Bali, where almost 200 countries are gathered to begin talks for a new climate accord.

The U.S. position puts it at odds with the UN and European Union, which support mandatory caps to curb global warming. Yvo de Boer, executive secretary of the UN Framework Convention on Climate Change, said earlier today he hopes the reduction goals remain in the text, which senior government officials from almost 200 countries will begin debating later this week.

``I really hope it's going to be in there,'' to give investors some guidance on likely emission constraints, de Boer said today to reporters after a press conference in Nusa Dua, on Bali.

Developed countries will be asked to make mandatory greenhouse-emissions cuts under a United Nations draft proposal to start off debate this week on a new global climate change treaty, a UN spokesman said.

UN Proposal

The UN will call for industrial nations to cut global warming emissions 25-40 percent by 2020, emerging economies such as China to agree to take measurable steps to reduce their own global warming pollution, and for a reduction in emissions from deforestation, according to Alex Cerniglia, a spokesman for the UN in New York. The proposal drawn up by a task group of countries including Australia and South Africa also urges emissions to be cut in half by mid-century.

The draft document -- which says terms for a new treaty should be agreed on by 2009 -- marks an opening salvo in what will be a multi-year negotiating process to forge a climate accord to replace the emissions-limiting Kyoto Protocol expiring in 2012.

The proposal will be presented to senior delegates from almost 200 countries gathered on the Indonesian island of Bali this week to debate both terms of a new treaty as well as whether formal negotiations should even start yet. The U.S. delegation will begin going through the UN plan in detail this afternoon, Watson said.

Other countries including Japan have expressed ``difficulties'' with the 25-40 percent emissions targets being included in the draft plan, Watson said.

`Not Alone'

``I think we will not be alone in having problems with defining numbers upfront,'' he said. The U.S., the only developed nation to reject the Kyoto climate change treaty, is open to the possibility of including legally binding limits on emissions, Watson said yesterday.

U.S. policy will change after the presidential election next year, said U.S. Senator John Kerry, a Massachusetts Democrat.

``When the Democrats win in 2008, the position will be different,'' Kerry said today in Bali. ``Every single Democratic candidate for president has embraced mandatory caps, has embraced the need for the United States to lead on these issues and has expressed their willingness to immediately become part of the Kyoto discussions and try to find a successive agreement.''

All major emitters, including the U.S., and developing nations such as China and India, should have binding targets in a new agreement, Canadian Environment Minister John Baird told reporters today in Bali.

Big Emitters

``For any successful fight against global warming, we need to get all of the big emitters on board,'' Baird said, adding that Canada supports the idea of having a collective goal split between nations in a ``differentiated'' way to account for differing capabilities and responsibilities.

Developing countries such as India and Malaysia have argued that talks shouldn't begin until industrialized countries do more to live up to prior commitments to help poorer countries deal with the threat of climate change.

China's per capita emissions will likely be less than half those in the U.S. in 2030, at 7.9 tons versus 19 tons, the International Energy Agency said last month. The European Union and the U.S. caused the build-up of the world's emissions, accounting for more than half of cumulative emissions from 1900 to 2005, while China and India contributed 8 percent and 2 percent, respectively, the IEA said.

`Not Efficient'

UN Secretary-General Ban Ki-moon said Dec. 7 that nations should adopt mandatory limits on greenhouse-gas emissions because ``our experience tells us that voluntary capping has not been efficient.''

The London-based Carbon Markets Association, a trade group representing Merrill Lynch & Co. and other investment banks, yesterday urged delegates in Bali to send a ``strong signal'' to markets by setting emissions guidelines for developed countries and spurring hundreds of billions of dollars in ``clean'' energy investments.

UN-led climate treaty negotiations must provide the financial community with a clear ``signal for them to be able to deliver the additional investments of up to $200 billion by 2030,'' Abyd Karmali, managing director at Merrill Lynch, said in a statement.

To contact the reporter on this story: Kim Chipman in Nusa Dua, Indonesia at kchipman@bloomberg.net; Mathew Carr in Nusa Dua, Indonesia at m.carr@bloomberg.net

Last Updated: December 10, 2007 03:48 EST