Tony Blair has said that he wants to continue leading the global battle against climate change after he steps down as Prime Minister.

Mr Blair said that he hopes to secure a global deal to curb greenhouse gas emissions at a G8 summit in June, which would be one of his last acts as Prime Minister and help to launch a new, post Downing Street career.

In his first explicit declaration of what he wants to do after he leaves No 10, Mr Blair said: “I’d certainly like to carry on working on it [climate change] after I leave office.”

His comments raise the prospect that he might carve out a role as a global campaigner against climate change similar, but with a higher profile, to Al Gore, the former US Vice President and presidential candidate.

Until now, Mr Blair has kept his post-Downing Street plans a secret, saying only that he wants to do something with a purpose. A climate change deal at the G8 summit in Germany would be seen as a key legacy of Mr Blair’s premiership. He launched the talks at the Gleneagles Summit, in 2005, when he held the G8 presidency.

Mr Blair, 53, told the Sunday AM programme on BBC One: “Fortunately, or unfortunately, I will leave office early enough to do something more with my life. I want to have something that’s got a real purpose to it, and climate change is certainly something that I am interested in. There are many other things too.”

He has previously hinted that his interest in Middle East peace and African poverty would outlast his tenure at No 10.

He insisted that the world was very close to a new climate change deal, including America, China and India, to come into force when the Kyoto Treaty expires in 2012. “It’s now that the real opportunity is there because I think there is a real change of mood in America,” he said.

Although he refused to be drawn on a leaving date, Mr Blair has previously said that he wants to attend the EU summit at the end of June, but will leave before the Labour Party conference in September.

Despite declaring that he was focussing on being Prime Minister, preparations have clearly begun for life after Downing Street. Martha Greene, a business associate, registered an internet domain last year for the Blair Foundation.

Mr Blair has also said that he will stand down as an MP after he leaves Downing Street, and plans to stay out of British politics for at least five years, giving a clear run to his successor. He is almost certain to write his memoires — for which he could earn about £10 million — and to take to the US lecture circuit.

— Mr Blair is to send an e-mail to the one and a half million people who have signed an online petition against road pricing, telling them that it is “surely part of the answer”. Writing in The Observer, he said that the petition had provoked a useful debate.

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