Prime Minister David Cameron wriggled and writhed in the Commons yesterday as he conceded that Britain will pay a shock EU bill — but not by the deadline.

The Tory leader came under fire from all sides for his failure to anticipate a £1.7 billion surcharge that he claimed had only come to light last week.

He declared the scale and deadline for the demand after a recalculation by the European Commission to be “completely unacceptable,” but evaded calls from his own back benches to refuse the bill outright.

“There is no pressing need for the money to be paid,” he said as he denied Britain would cough up by December 1.

“The numbers are a provisional estimate.”

Mr Cameron added that no decision on payment would be made before the government had had a chance to “crawl through this in exhaustive detail.”

Pro-EU Labour leader Ed Miliband was only able to offer a lightweight challenge.

Describing the European Commission’s handling of the issue “cackhanded and unacceptable,” he sought to embarrass the government for not anticipating the £1.7bn demand.

But Mr Cameron batted away the attack, repeatedly claiming that the precise amount only emerged last week.

It was left to anti-EU Labour backbenchers to try to pin the PM to the ropes.

Blackley and Broughton MP Grahame Stringer urged a Commons vote to debate any eventual payment once the government’s calculations had been completed.

“If it is outside the norms, will the PM give this house a vote?” he demanded.

Mr Cameron replied that “I’m always happy to have votes in this house” but added that he had no intention of calling one himself.

Glasgow South West MP Ian Davidson challenged him to commit to a parliamentary vote, asking: “Would it not be helpful to his own position if he would agree to bring back for a vote in this house the amount that he was finally agreeing to negotiate?”

But the PM blustered: “I think we’re some way away from that.”

And he had no answer to a challenge from Labour Blythe Valley MP Ronnie Campbell, who asked: “Why does he not grasp the nettle and have the referendum the day of the election next year and let the people decide?”