Aid agencies have expressed concern at the failure of the G8 leaders to make significant moves forward on climate change.

Talks on how to reduce greenhouse gases dominated the second day of the summit in Japan Wednesday.

The world's leaders did little more than re-state agreements made at last year's summit in Germany. Last year, the G8 leaders agreed to "seriously consider" carbon emissions cuts of at least 50 per cent by 2050.

This year the leaders of the world's eight richest countries - Britain, France, Germany, Italy, Russia, Canada, Japan and the US - agreed only to "consider and adopt the goal of achieving at least 50 per cent reductions in global emissions by 2050".

Campaigners had hoped for interim cuts in carbon emissions that they believed would show a commitment to combat global warming.

Oxfam said that the outcome "could leave us with a 50/50 chance of a climate meltdown".

"Rather than a breakthrough, the G8's announcement on 2050 is another stalling tactic that does nothing to lower the risk faced by millions of poor people right now."

Calling the statement "very disappointing", Tearfund's Peter Grant said, "To do little more than re-state last year's G8 commitment to halve emissions by 2050 is a very disappointing outcome, demonstrating a lack of leadership and vision.

"The science is telling us that merely halving emissions is no longer enough."

Friends of the Earth slammed the climate change communiqué, calling it "totally inadequate". The G8 had shown "total disregard for their own responsibilities towards the rest of the world", said spokesperson Karen Orenstein.

There was less criticism over the G8's announcement about increasing aid. It followed a meeting between summit heads and seven African leaders on Monday.

On Wednesday, the G8 agreed to fulfil its promise - made at the Gleneagles summit in 2005 - to increase aid by $50 billion a year by 2010. Half of this will be to Africa.

Grant said, "No extra commitments were needed from the G8 on aid. But with only two years to meet this target, an extraordinary effort is required to deliver on existing promises.

"High food and fuel process are crippling for those who already live a hand-to-mouth existence. This is not the time to step away from hard fought commitments to help the world's poorest people."

Aid agencies claim that G8 countries are likely to fail to meet their targets for aid by as much as $30 billion.

The long-term campaigner, Sir Bob Geldof, endorsed this view. Speaking at the summit, he said, "This is the halfway point to 2010, which is when the Gleneagles promise comes up, and they should be 50 per cent of the way there, but in fact they are 14 per cent of the way there."