Nick Clegg will warn Tories not to put Britain's recovery at risk by rowing back from environmental commitments as Government advisers said emissions targets should not be watered down.

The Committee on Climate Change said there was presently "no legal or economic basis" to amend the UK's legally binding greenhouse gas reduction totals for the period 2023 to 2027.

In an intervention likely to reignite coalition conflict on the issue, the panel of experts said sticking to the target was the "minimum" the UK needed to contribute to global action.

Chancellor George Osborne has warned the UK risks pricing itself out of international markets if it gets "out there in front of the rest of the world" and must keep green measures under review.

He backs a future energy strategy which could see the UK construct up to 40 new gas plants - putting it at risk of breaching the existing targets.

Delivering the Green Alliance Leadership Lecture in central London, Mr Clegg will claim only his party remains committed to the green agenda, saying: "The green consensus across the political parties is, I'm afraid, falling away."