Extra aid to help dig Africa out of poverty agreed in July by leaders of the world's main industrial nations could be eaten up by global warming unless urgent action is taken, a British scientist said on Monday. In an open letter to environment and energy ministers of the Group of Eight (G8), Lord May of Oxford, president of the Royal Society scientific think-tank, said the deal struck at the G8 summit in Gleneagles was flawed. "As long as greenhouse gas concentrations continue to rise, there is the very real prospect that the increase in aid agreed at Gleneagles will entirely be consumed by the mounting cost of dealing with the added burden of adverse effects of climate change in Africa," he wrote.