The Prince of Wales yesterday described climate change as the gravest challenge facing man - and became embroiled in a row with America about the urgency of tackling it.

In an interview Prince Charles, who starts an eight-day visit to the US next week, called for world leaders to treat climate change with "a far greater degree of priority" than they were at present.

He told Radio 4's Today programme: "I don't want my grandchildren, if I'm still alive by then, to say why didn't you do something about it when you could have done."

Prince Charles was backed by Sir David King, the Government's chief scientist, but a senior US official later responded by saying that the Bush administration did not believe that climate change was the most important issue facing mankind.

"We believe there are a number of important issues, and we have to deal with all of them. We can't just pick one and drop everything else," said Vice-Admiral Conrad Lautenbacher, undersecretary of commerce for oceans and atmosphere.

The vice-admiral was in London to attend a Royal Society conference on climate change. Asked whether the unusually intense hurricanes battering the American coast this year were consistent with man-made global warming, he said this was "an attractive hypothesis" but that the US administration's view was that natural cycles for hurricanes - and this is a rising one - were much stronger than the gradual increase likely from any warming trend.