Ed Miliband tore into David Cameron yesterday for giving up the fight against climate change, with the recent disastrous flooding the result.

The Labour leader said the winter storms should serve as a "wake up call."

Two people died on Friday - James Swinstead, a passenger on a cruise ship in the English Channel, and minicab driver Julie Sillitoe, whose car was hit by falling masonry in central London.

And on Saturday a pregnant woman from Tredegar, South Wales, died in a crash on the A465 between Brynmawr and Garnlydan.

Mr Miliband said the PM was now portraying climate change merely as "a matter of conscience," when previously it had been a "core conviction" while in opposition.

Referring to a series of extreme storms, Mr Miliband told the Observer: "If you keep throwing the dice and you keep getting sixes then the dice are loaded. Something is going on.

"We have always warned that climate change threatens national security because of the consequences for destabilisation of entire regions of the world.

"But the events of the last few weeks have shown this is a national security issue in our own country too, with people's homes, businesses and livelihoods coming under attack from extreme weather. And we know this will happen more in the future."

He said he had "genuinely believed" that Mr Cameron was sincere about his passion for green issues, but the sacking of Charles Hendry as Energy Minister and the appointment of Owen Paterson - a climate change denier - as Environment Secretary suggested otherwise.

"The reality is that the action we take as a country depends on whether you believe in climate change," he said.

"If you believe that the climate has been changing for centuries and that this is no different then why would you believe that it is necessary to take all the measures that are required?

"What we have seen for the last couple of weeks is that that (attitude) has impacts.

"So when the government downgrades flood protection, cuts the floods budgets, cuts the adaptation budget - all of those things (have) an impact."