Tony Blair is to lead an international campaign to cut carbon emissions by 50 per cent by 2050.

The latest addition to the former Prime Minister’s portfolio of interests has the backing of the White House, the UN and Europe, and Mr Blair is shortly to discuss the plans with the Chinese and Indian Governments.

Just last month it was announced that Mr Blair is to be a part-time adviser to JP Morgan Chase. There is also his work, ten days a month, as envoy for the Quartet of the EU, US, Russia and the UN in the Middle East — and an interfaith foundation to be set up later this year.

Now it has emerged that Mr Blair, whose venture has the support of Gordon Brown, has been working on the climate change project with a group of experts since he left office last summer. He will publish an interim report to the G8 group of industrialised nations in a few months.

He said: “The fact of the matter is that if we do not take substantial action over the next two years, by 2020 we will be thinking seriously about adaptation rather than prevention.”

Backed by The Climate Group, a not-for-profit organisation supported by business, Mr Blair is drawing together an international team. These include Sir Nicholas Stern, the author of the report on the costs of climate change. Specialists from China, Japan, the US and Europe are also on board.

In an interview with The Guardian, Mr Blair said: “This is extremely urgent. A 50 per cent cut by 2050 has to be a central component of this. We have to try this year to get that agreed, because then you have something for everyone to focus upon. We need a true and proper global deal, and that needs to include America and China.”

He went on: “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.”

“People often say to me there are lot of climate change plans out there and I say ‘how many of them are politically do-able?”, Mr Blair said. “So the experts are providing technical knowledge and specialist insight but what I am trying to do is guide it politically.”

A new climate change deal needs to be agreed by the UN by the end of the year to replace the Kyoto treaty, which expires in 2012.

Mr Blair said: “Essentially what everyone has agreed is that climate change is a serious problem, it is man-made, we require a global deal, that there should be a sustainable cut in emissions at the heart of it, and this global deal should involve everyone, including in particular America and China, so it is the developed and the developing world.

“The question is, what is the framework that gets everyone in the deal?”

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