The prime minister's record on the environment has come under fire from the Liberal Democrats.

In a speech at the party's London headquarters, leader Charles Kennedy accused Tony Blair of failing to use the UK's "special relationship" with the US president George W Bush to encourage his participation in the Kyoto treaty on climate change.

His comments came ahead of next month's European parliamentary elections, in which Labour are expected to fare badly.

"Labour has failed us on environmental issues. It has failed at local level, it has failed nationally, and it has failed on the world stage too," he said.

"Mr Blair claims to be close to President Bush. But on this, as on so many things, that relationship has not benefited the environment.

"When the Bush administration - representing a country with five per cent of the world's population but accounting for a quarter of all CO2 emissions - refuses to take seriously even the proposition of climate change, it is gambling with all our futures. 

"It is time that the European Union stepped into the vacuum that the US is leaving and leads the push to raise environmental standards world-wide. 

"The environment should be a priority for Britain in Brussels. A vote for the Liberal Democrats is a vote to ensure that it is."