Britain, France and Germany have unveiled proposals for an international conference on Afghanistan later this year in order to press Afghans to take more responsibility for their own country.

"What is important, and this is our joint view, is to apply pressure in order to find a way to get the Afghans to appreciate that they have to take responsibility step by step," Chancellor Angela Merkel told a joint press briefing with Prime Minister Gordon Brown on Sunday.

The conference, the location of which is yet to be decided, "is to create some momentum and to say that we are now coming to a transitional phase following the second presidential election" in Afghanistan, she said.

With the help of an upcoming review by the new US and NATO commander in Afghanistan, General Stanley McChrystal, it will make clear to countries involved in Afghanistan "what job they have to do and what our common aim is", Merkel said.

"The Afghan government will then know what growing responsibilities are going to be coming their way," she said, "and of course so that the international engagement ... can be reduced."