An increasing number of backbench MPs are clamouring for the resignation of British Prime Minister Gordon Brown in the wake of the Labour party's humiliating defeat in Thursday's European parliamentary poll as well as local council elections.

The prime minister's party took just 15 percent of the European vote, putting it in third place behind the Conservatives and the anti-EU UK Independence Party. In the local council elections, Labour lost control of its last four councils, putting in its worst performance since 1910. In a further blow, an 11th minister resigned today.

Crunch time could come this evening; Prime Minister Brown will be holding his regular meeting with MPs in the House of Commons and the chorus of voices calling for his resignation is growing louder. Mr Brown has vowed to fight on but if 70 MPs sign a motion calling on him to step down, he will have to go.

Downing Street insiders say some rebel MPs might be willing to stop publicly attacking Mr Brown if he agrees to a secret motion-of-confidence ballot and he wins. The embattled prime minister has reportedly attempted to placate backbenchers by promising an enquiry into the Iraq war and shelving plans to partially privatise the postal service.