The UK government is not doing enough to tackle climate change, according to a report by a parliamentary committee.
Action is needed on greenhouse gas emissions, MPs say
The Environmental Audit Committee attacked ministers for believing that new technology and market mechanisms will reduce greenhouse gas emissions.
The committee says Britain and the developed world need to reduce emissions by 60-80% by 2050.
Committee chairman MP Peter Ainsworth called on the government to draw up a clear plan of action.
In its report, the parliamentary committee attacked the European Emissions Trading Scheme, which is central in helping the EU to bring down greenhouse gas emissions.
Plan of action
The BBC's environment correspondent, Richard Black, said the committee found the scheme's regulations were too lax, had minimal impact on emissions and might lead to windfall profits for electricity generators.
He said the government was currently embroiled in a legal dispute with the European Commission over Britain's emission allowances under the scheme.
This was a dispute which the audit committee said risked "wantonly squandering" Britain's reputation for leadership on climate change, he reported.
The committee believes Britain and the rest of the developed world need to reduce dramatically their emissions, but this cannot be achieved by technology and market mechanisms alone.
MP Peter Ainsworth, speaking on BBC Radio Five Live, called for a plan of action.
"The government chief scientist and Tony Blair have both said that climate change is one of the most serious problems facing mankind, and Tony Blair has rightly put it at the head of his international agenda," he said.
"The trouble is that the rhetoric isn't translating into action."
He said Britain needed to provide clear policies to direct the international community.
"What Britain needs to do is to set out a list of achievable goals for the world community, which involves getting America engaged with this as far as is possible; but it also crucially involves getting the developing world involved.
"The time for talking about this problem is drawing to an end; what we really do need now is a programme for action, and that's what we're trying to impress on the government through this report."