While British Prime Minister Tony Blair is reportedly urging Bush to rejoin international efforts on climate change, diplomats in Buenos Aires are also extending an olive branch to their US colleagues.

"The United States is responsible for 36 percent of emissions of industrialized countries or 25 percent of the global total. So if you want to make a push you have to go for 100 percent," said Raul Estrada, head of the host Argentina delegation.

Estrada, who was chairman of the 1997 conference in Kyoto that created the protocol, has proposed two seminars for next year and already has the support of the European Union, the heavyweight in global climate talks.

"By having this broad discussion, I think we are offering them (the United States) an opportunity to participate and we would be very keen to see them do that," Yvo de Boer, head of the EU delegation.

Since the conference opened Monday, the United States has made its position clear: it has chosen a "different path" from Kyoto and will continue to focus on a domestic emissions program to 2012 that does not threaten economic growth.

On Friday, it voiced its clear opposition to the seminar proposals.

"We felt they were very tightly linked to the start of a post-2012 negotiating process and we believe it is premature to start such activity," US delegation head Harlan Watson said in an interview.

The UN talks go to a higher level on Wednesday, when 80 environment ministers meet for three days.

'TALKING ABOUT TALKING'

While seminars may sound small in the grand scheme of climate change talks, many negotiators say the proposal is a refreshing look forward.

They note that climate change talks were practically paralyzed for the last three years, since the United States pulled out of Kyoto and before Russia ratified the protocol last month, allowing it to go into force on Feb. 16.

"The seminars would be a big step. It would be the first formal opportunity to exchange views on the future ... in the last three to four years," said a UK negotiator, who asked not to be identified.

Developing countries, which were excluded from Kyoto, would also benefit from the seminars, the negotiator said.

Industrialized countries are required under Kyoto to cut their greenhouse gas emissions by 5 percent in 2012 versus 1990 levels. But even the staunchest backers say it is just a first small step in the fight against global warming.

Environmental activists at the conference expressed frustration with the slow pace and the seminar proposals.

"I think it is a sad comment that it is the best we can do at this point," said Steve Sawyer, climate and energy specialist for Greenpeace.

The EU's De Boer recognized that the man on the street "might wonder why we are having endless discussions talking about talking about the future."