New York ? Former British Prime Minister Tony Blair says he hopes to break the “deadlock” in global climate talks with evidence that 10 million jobs could be created by 2020, if developing nations agree to big cuts in greenhouse gases.

Blair, heading up a climate initiative, released a report that also shows a global climate agreement could increase the world’s GDP by 0.8 percent by 2020, as compared with the projected gross domestic product with no climate action.

He was visiting New York ahead of a U.N. climate summit drawing 100 world leaders on Tuesday and a flurry of supporting events in New York City this week.

The events are intended to build support for crafting a new climate deal in Copenhagen, Denmark, in December to replace the 1997 Kyoto Protocol, requiring mandatory cuts in atmospheric warming gases, that expires at the end of 2012.

Blair’s report, one of a series he is promoting, is based on computer modeling by Cambridge University economists. He called the upcoming Copenhagen negotiations “the moment when we move from a campaign to a policy program” that clears the hurdles of exactly how the world’s main economies will cut emissions of carbon dioxide, methane and other industrial warming gases.

“I think it is essential that we get an agreement at Copenhagen,” Blair said Sunday during a meeting with a small group of reporters at a Manhattan hotel. “I think it is possible, and the purpose of the report is to show that in economic terms, certainly in the medium and long-term, it’s hugely to our economic benefit to get a global agreement.”

In the shorter term, not so much. Blair acknowledged the costs of investment in new forms of energy that emit fewer warming gases — wind, solar panels, nuclear power, electric vehicles, so-called “smart grid” plans using more renewable forms of energy — are daunting, particularly on the heels of a global financial crisis.