Gordon Brown yesterday urged some coalition partners to make a "bigger contribution" to frontline fighting in Afghanistan as he made clear he would not set an artificial timetable for British troop withdrawal.

The Prime Minister faced a call from Jeremy Corbyn, the left-wing Labour MP, to rethink strategy with a view to the withdrawal of British troops "as soon as possible".

At Commons Question Time, the London MP said more than 2000 Afghans had died this year alone and the war would cost British taxpayers £1.6bn.

"Don't you think there's a need for a re-examination of our strategy?" he asked Mr Brown. "We've been there seven years. The poppy crop is at record levels. Wouldn't it be better to start buying the poppy crop so it could be used for medicinal purposes and not for the drug trade, to undermine the basis of the instability there and set a timetable for political dialogue that ensures we can withdraw British troops as soon as possible?"

The PM replied by insisting the responsibility for the violence and death in Afghanistan lay with the Taliban and their supporters. He explained that 58,000 soldiers with the Afghan army had been trained and the police were now training 80,000 Afghans.

"As their capability improves we will not only allow Afghan forces to take more control over their own country but local and national government will be more secure and the economic and social development programmes we are engaged in will happen too.

"We have doubled the number of poppy-free provinces in the last period of time. We are continuing to fight the war against heroin as well."

Bob Russell, the Liberal Democrat MP for Colchester, pointed out how 43 nations were involved in the coalition but that the number in southern Afghanistan could be "counted on the fingers of one hand".

The back bencher asked: "Isn't it time our European allies did more to send their troops to the front line and not rely on Britain to take the brunt?" The PM said he agreed that every country, which had signed up to the coalition forces should make a contribution, stressing: "In some cases, a bigger contribution than they are making at the moment."

He told MPs how the French had agreed to put extra forces in Afghanistan and these would allow the American marines to move south to Helmand province while the Germans were offering support with policing, which would help increase dramatically the number of police being trained.

"But I agree," added Mr Brown, "all countries who have signed up to this venture should make the fullest possible contribution."

In Vienna, US General John Craddock, Nato's Supreme Allied Commander of Europe, said more helicopters, surveillance aircraft and unmanned aerial vehicles were needed in Afghanistan to support the armed forces there. He also made clear he wanted national governments to reduce or drop restrictions on how and where troops from their countries could be used in the alliance's Afghanistan mission.