The world's top 20 polluters gathered here Friday amid hopes that their talks can help break a deadlock and add momentum to negotiations on a successor to the Kyoto Protocol.
  
Former British prime minister Tony Blair, who launched the so-called Group of 20 (G20) initiative on global warming in 2005, was in Japan as the head of a new team of international experts tasked with securing a climate deal.
  
Blair's team, backed by the United States and Europe, will issue reports on the remaining differences among major countries ahead of a UN-backed goal to seal a post-Kyoto deal by the end of 2009.
  
"There is a deadlock. Everyone is agreed where we want to get to, but unless you agree on the framework for getting there, you are left with a process and not a result," Blair told The Guardian newspaper in London before heading to Japan.
  
The United States has resisted EU-led calls for binding international goals on cutting greenhouse gas emissions, which are blamed for warming that could have catastrophic consequences for the planet in coming decades.
  
Blair, who stepped down as prime minister last year after 10 years in power, said he thought he could prepare a framework for a 50 percent cut in carbon emissions by 2050.
  
Last year's summit of the Group of Eight major economies agreed to seriously consider that goal. But Blair said it was important to agree on a deal that included the United States and China, the world's two biggest polluters.
  
"The fact of the matter is that if we do not take substantial action over the next two years, then by 2020 we will (be) thinking seriously about adaptation rather than prevention," he said.
  
Blair held talks here Friday evening with Japanese Prime Minister Yasuo Fukuda and was due to address the opening of the G20 talks on Saturday in suburban Tokyo.
  
Japanese Environment Minister Ichiro Kamoshita hoped the weekend meeting would ensure progress at July's summit of the Group of Eight major industrial nations, which will take place in the northern Japanese mountain resort of Toyako.
  
"I will work hard so that the meeting will set an overall tone of discussions that will lead to the Toyako summit in July," Kamoshita told reporters.
  
He said the G20 meeting will share ideas on "a reasonable solution to create a (post-Kyoto) framework in which all countries can participate."
  
The G20 meeting is being attended by senior officials from the Group of Eight -- Britain, Canada, France, Germany, Italy, Japan, Russia and the United States -- and emerging economies such as Brazil, China and India.
  
Blair as premier initiated the G20 dialogue on the environment as a way of bringing together the United States, the main opponent of the Kyoto Protocol, as well as developing countries that have no obligations under the treaty.
  
But the United States and developing countries all agreed at a December meeting in Bali to take part in negotiations on drafting a successor to Kyoto, whose obligations end in 2012.
  
The G20 meeting comes ahead of the next round of negotiations on a post-Kyoto deal to be held at the end of the month in Bangkok.
  
US President George W. Bush argues that Kyoto is unfair as it makes no demands of fast-growing developing countries.
  
Japan wants the talks here to focus in part on ways to share with emerging economies technology to improve energy efficiency.
  
"Delays in measures to tackle climate change in developing countries could become a major hurdle to sustainable development," said a report by a Japanese government panel to be issued at the G20.