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World leaders last night hailed a groundbreaking deal paving the way for a “substantial” reduction in greenhouse gas emissions with a view to halving them by 2050. The compromise agreement fell short of the original aims of Angela Merkel, the German Chancellor, but was more ambitious than many expected.

It was clinched after President Bush was persuaded that his own plan for a climate change conference in the autumn would be part of efforts to reach a global agreement through the UN. Against expectations, he also allowed the 50 per cent target shared by most leading industrial countries to appear in the final G8 communiqué. Some saw Mr Bush’s shift as a parting gift to Tony Blair after their last one-to-one meeting.

Mrs Merkel and Mr Blair called the agreement a “huge success”, emphasising that America was now at the heart of the attempts to reach a worldwide deal to succeed the Kyoto Protocol in 2012. Some campaigners welcomed the compromise as an important advance; others said it was weak and did not go far enough because they omitted the target of limiting temperature increases to 2C (3.6F).

It’s Grrrrr8 (honest)

As the G8 summit begins in Germany, Hugo Rifkind explains everything you need to know – and lots of stuff you don’t

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• Video: Our young man in Heiligendamm

• Audio: Behind the scenes at the G8

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BACKGROUND

• Quotes: what Putin told The Times

• Blair reinvented the Middle Ages

• The West is starting this Cold War

• Save the planet: give to China

Related Internet Links

• Official site of the G8 summit Heiligendamm

Related Links

• Bush hit by stomach complaint at summit

• A Change of Climate

• Global warming is the big debate in America, too

Multimedia

• Video: Our young man in Heiligendamm

At the summit on the Baltic coast, Mrs Merkel said she was “very, very satisfied” with the pact but acknowledged that the accord was a compromise that fell short of her hopes for a binding deal. “Many countries moved on this issue,” she said. “The very best we could achieve has been achieved.”

The UN called the deal a step towards a broader, worldwide pact by 2009. But Greenpeace said the deal was clearly not enough to prevent dangerous climate change. Mr Bush is still not committed to achieving the 50 per cent cut in emissions on 1990 levels but has agreed to give it “serious consideration”.

A British official said: “There is no reference to any other proposal in the deal, so 50 per cent must be the starting point of the discussion in the autumn.”

The US insisted that its agreement was dependent on China and India, two other major polluters, also signing up to progress in the UN process.

Mr Blair was asked by Mrs Merkel to put the draft agreement to Mr Bush at their breakfast meeting yesterday and he went along with most of it. Officials saw that as clear evidence that Mr Blair’s often criticised close relationship with Mr Bush has yielded positive results. He declared that the deal would have been been unimaginable just a few years ago.

Leaders of the G8 nations agreed that greenhouse gas emissions should stop rising “followed by substantial global emissions reductions”. In setting a global goal they would “consider seriously” the decisions made by EU countries, Canada and Japan to halve emissions by 2050.

Mr Blair said it had been accepted “that we need a new worldwide agreement on climate change” and that at the heart of that should be a substantial reduction in greenhouse gas emissions. He emphasised: “There isn’t going to be an agreement until it’s got America and China in it. There’s now a process to achieve that agreement.”

Asked if he was disappointed that there was no specific commitment to halving emissions, only serious consideration given to that goal, Mr Blair replied: “What does substantial mean? . . . What you have got is a sense that a substantial cut in emissions is of the order of a halving of emissions.”

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