Relations between the coalition parties hit a new low today, as rows over free schools and green levies saw the Liberal Democrats and Conservatives at loggerheads.
Tory anger at Nick Clegg's attack on free schools was evened-out yesterday when the prime minister appeared to make an off-the-cuff commitment to rolling back green levies on energy bills – a policy the Liberal Democrats strongly oppose.
"It wasn't something I was expecting and it's not something I fully agree with," Clegg told the BBC.
"I'm not quite sure what 'rolling back green levies' means.
"Of course I'm certainly not going to accept - I don't think anyone would want us to accept - simply scrapping a whole system of levies, which for instance help two million of the poorest households in this country.
"We need to strike a difficult balance between getting bills down, keeping the lights on and investing in green jobs."
Downing Street insisted the policy had been agreed between the two parties over recent weeks and would be set out in greater detail in December's autumn statement.
But there were suspicions the policy was thrown together at the last minute by Cameron as he faced one of his worst PMQs as prime minister.
"Yesterday was the day David Cameron lost control of his government," Ed Miliband told Federation of Small Businesses.
"In weakness and panic, he made up a policy on energy which means business as usual for the energy companies and which is already falling apart."
The Labour leader also attacked Clegg for suggesting the government could shift the burden of green levies into general taxation.
"Today, Nick Clegg has revealed their true intentions," he said.
"To shift the burden from ordinary bill payers, like you, to ordinary taxpayers, like you. Governments have always looked at this balance but this government wants you to pick up the tab for its failure to stand up to the energy companies."
As the confusion over the green levies plan threatened to poison coalition relations, senior Tories were reacting with astonishment at the strength with which Clegg was pursuing his new crusade against free schools.
The deputy prime minister deliveried a speech today demanding that all teachers at free schools are qualified and that basic standards – especially for food – are also forced on the new institutions.
"This idea that greater freedom means no core standards, in my view, is a nonsense," he said.
"Although we work well with the Conservatives, our two parties still have differences of opinion - some strongly held.
"I'm perfectly entitled to talk without being shouted down about what my vision of the future of the school system should be.
"And looking to the future, there are aspects of schools policy currently affected by the priorities of the Conservative party which I would not want to see continue.”
Clegg also called for a 'parental guarantee' that all schools meet core standards in teaching and care.