The UK must appoint a climate change minister with the power to cut across departmental turf wars if it is to meet its emissions reductions targets, according to a major new report from the Environmental Audit Committee (EAC).

Released on the same day as environment minister Hilary Benn is due to give his response to the consultation on the draft climate change bill, the Structure of Government and the Challenge of Climate Change report warns that the government's "confused" climate change policy is jeopardising its position as a world leader on global warming.

It raises fears that the government is likely to miss its target of cutting carbon emissions by 20 per cent by 2010 and calls for the appointment of a new Climate Change and Energy secretariat and a cross departmental climate change minister to lead policy and limit inter-departmental conflict.

The committee, which has been a consistent critic of the government's contradictory climate change policy, warned that without such leadership there was a danger that while some areas of government move to reduce carbon emissions other departments are implementing policies, such as road and airport expansion, that will increase emissions.

The EAC's chairman Tim Yeo highlighted Gordon Brown's house building plans as another area where progress on climate change could be undermined without proper integration between different departments. "It would be disastrous if bad planning policy meant that today's new developments become tomorrow's climate slums," he said.

The report comes as Hilary Benn today prepares to release his response to the consultation on the government's draft climate change bill ahead of the expected publication of the full bill next month.

The EAC and environmental groups have broadly welcomed the bill, which aims to impose legally binding emission reduction targets upon successive governments to ensure a 60 per cent cut in emissions by 2050.

However, they have also urged Benn to toughen up the bill by introducing stronger policing mechanisms, extending it to cover aviation and shipping, and imposing stricter annual emission reduction targets designed to deliver an 80 per cent cut in emissions by 2050.

"If the Government has been listening to what scientists, MPs and the public have been telling them during the consultation Hilary Benn will be announcing a beefed up Bill," said Friends of the Earth Director, Tony Juniper. "If this Bill is going to be effective it needs to commit the UK to cutting emissions by at least three percent annually and it has to include emissions from all sectors including aviation and shipping."