|PIC1|The first climate change Bill is due to be published by ministers, aiming to cut Britain's carbon dioxide emissions by 60 percent by the year 2050.

The Bill will introduce legally-binding reductions in harmful greenhouse gas emissions.

Prime Minister Tony Blair, Chancellor Gordon Brown and Environment Secretary David Miliband will launch the legislation in Downing Street.

Miliband has rejected opposition calls for annual targets on reducing emissions.

"Changing your policy on the basis of one year's weather isn't a sensible way of doing things," he told the BBC.

"We think it's right that every five years we set carbon budgets in legislation, that we give business confidence about a 15-year period ahead so that we can really invest for the future," said Mr Miliband.

"Instead we need a framework of legislation which gives real confidence to business and to individuals about the way in which our country's going to change to meet the climate change challenge."

Christian Aid's senior climate policy officer, Andrew Pendleton, said: "Mr Miliband is to be congratulated for publishing the bill and he is right to be proud of it - he and the government are an example to the rest of the G8.

"But if the final legislation is not significantly stronger, the process would represent a massive lost opportunity. It is the first step on a long journey rather than the destination itself."

Ahead of the publication, shadow environment secretary Peter Ainsworth said: "David Cameron has pushed climate change to the top of the political agenda.

"But this is too important an issue for normal party politics. We want to work with the Government and other parties to get the right framework in place. However, we do not want a watered-down Bill."