Sikorski said: "The 1,600 troops that we are deploying in Afghanistan right now is the most that we can do this year, but we are adding eight helicopters and will be spending in the region of a few million dollars on assistance training."

Polish troops will also continue to train Afghan armed forces, while they will be charged with security along a 300km stretch of road between the capital Kabul and Kandahar.

Poland sent its troops, which are scattered across five different regions in central and southern Afghanistan, as part of a UN mission in 2002.

More than 70,000 international troops are based in Afghanistan fighting Taliban forces.

Fighter sought

Sikorski also called for Gulbuddin Hekmatyar, an Afghan fighter leader, to be tried for allegedly killing two journalists, including a BBC cameraman murdered 21 years ago.

The Afghan government has shown willingness to talk to Hekmatyar and other fighters, including from the Taliban, in a bid to end the violence in the country.

However, Rangeen Dadfar Spanta, Afghanistan's foreign minister, said Kabul would not bend to Hekmatyar's demands for international troops to first leave the country.

Sikorski said: "I wouldn't dream of interfering in any country's internal affairs but with your permission the name of Hekmatyar was mentioned so allow me to make a personal comment.

"I believe Mr Hekmatyar has not been brought to justice for either of his crimes and I hope he will."

The Polish minister said that one of the men, cameraman Andy Skrzypkowiak, had been a "personal friend" of his.

Hekmatyar's fighters allegedly killed Skrzypkowiak in 1987 and an Afghan reporter in 1993.

The fighters are also said to have assassinated many other individuals and political opponents.

Hekmatyar, a former commander of the 1978-1989 anti-Soviet resistance, is involved in fighting against the Western-backed government in Kabul.

He is wanted by both Kabul and Washington.

Sikorski is an old Afghanistan hand, having spent time there as a war correspondent in the 1980s covering the Afghan offensive against the occupying Soviet army.