Charles Kennedy has challenged the leaders of the other major parties to sign up to a series of tough climate change targets.

As the Kyoto protocol came into force on Wednesday, the Liberal Democrat leader wrote to Tony Blair and Michael Howard urging them to go even further than the environmental pact.

Government Response: Department for Environment, Food and Rural Affairs

Margaret Beckett , secretary of state for environment, food and rural affairs said: "Today is the historic commemoration of a huge achievement which rightly bears the name of the city of