British Prime Minister David Cameron urged eurozone leaders today to sort out their debt problems soon or risk the collapse of the single currency as they grapple with the crisis in Greece.

Cameron's comments were his most pessimistic yet on the issue and are sure to annoy European leaders who were angered by the refusal last year of Britain, which does not use the euro, to endorse a new EU fiscal treaty.

"It either has to make up, or it's looking at a potential break-up," Cameron said in his weekly question-and-answer session in parliament.

"That is the choice they have to make and it's a choice they cannot long put off," he added.

"If the eurozone wants to continue as it is then it has got to build a proper firewall, it's got to take steps to secure the weakest members of the eurozone, or it's going to have to work out it has to go in a different direction."

Fears that Greece could be forced out of the eurozone have rocked the financial markets after voters earlier this month deserted the main parties that had supported tough measures included in an EU-IMF bailout.

Greece will go to the polls again on June 17 after the May 6 poll failed to produce a government.

British officials have said that they are making contingency plans for a possible break-up of the eurozone.

The British leader meanwhile said he hoped to discuss European growth with new French president Francois Hollande when they have bilateral talks before this weekend's G8 meeting in the United States.

"I look forward to specifically discussing what more we can do to help in terms of European growth," Cameron said, adding that he would focus on steps to improve the single market.

Cameron was responding to a jibe from opposition Labour leader Ed Miliband about the fact that the premier snubbed Hollande when the then-challenger for the French president visited London earlier this year.