The Conservatives and the Liberal Democrats presented a united front today when they called on the new environment secretary to join their climate change consensus.
They welcomed David Miliband to his new job and urged him to join their agreement, also signed by Plaid Cymru, the SNP and the DUP, calling for annual carbon emission cuts, monitored by an independent body, and a more ambitious long-term target.
Their call comes after a brief spat between the two parties yesterday when neither could agree who had called for a meeting between David Cameron and Menzies Campbell to discuss the issue.
The Lib Dems said Sir Menzies wanted to challenge the new Tory leader on his green credentials, with environment spokesman Chris Huhne saying there had been a "string of contradictions between David Cameron's green words and his party's blue actions".
He cited the Witney MP's support for road-building as one example, concluding: "For the consensus to work we need clear policy commitments from David Cameron's Tories, not just warm words."
But shadow environment secretary Peter Ainsworth hit back saying it was "disappointing" that Mr Huhne had "chosen to play party politics with the serious issue of climate change".
He added: "We will continue to work constructively with politicians from any other party that is prepared to put the environment at the very top of its agenda."
Today, however, both sides appeared to have put aside their differences when they urged Mr Miliband to agree to their agreement in recognition of the "need for political parties to work together as far as possible to meet the challenge of climate change".
Their letter was sent after the new environment secretary this morning called for a "new environmental contract" on tackling climate change to ensure government, business and individuals all play their part.
"The old system of 'too much take and too little give' is bad for the planet, bad for business and bad for the most disadvantaged," he said.
"The challenge we face is to marry economic growth, social justice, and environmental sustainability. They can and must go hand in hand."
Mr Ainsworth and Mr Huhe welcomed this as being potentially "very helpful", writing: "The threat of climate change, as you rightly recognise, is difficult to counter precisely because emissions come from every sector of the economy: from individuals, from business, from industry and from agriculture."
They noted that offers of help from opposition parties "are not always well intended", but insisted their offer was not on a "take it or leave it basis", and said the continued debate about the issue was inevitable and "arguably right in democratic terms".
It is unlikely their offer will be accepted, however - while the government insists it is doing a huge amount to tackle climate change, particularly on an international level, Tony Blair has said the introduction of annual carbon targets would be impractical.