Western powers now in Afghanistan run the risk of suffering the fate of the Soviets if they cannot halt the growing insurgency and an Afghan perception that they are foreign invaders, according to Zbigniew Brzezinski, the former national security adviser to Jimmy Carter.

In a speech opening a weekend gathering of military and foreign policy experts, Brzezinski endorsed a British and German call, backed by France, for a new international conference on Afghanistan and set the tone for a sombre assessment of the situation. He noted that it took about 300 US Special Forces to overthrow Taliban rule after the September 11 attacks in 2001.

Now, however, with some 100,000 US and allied troops in Afghanistan, those forces are increasingly perceived as foreign invaders, much as the Soviets were from the start, Brzezinski said.

Afghanistan is the issue in Obama’s foreign policy that has “perhaps the greatest need for strategic review,” Brzezinski said. “We are running the risk of replicating — obviously unintentionally — the fate of the Soviets,” Brzezinski said on Friday night.

The presence of so many foreign troops underpins an Afghan perception that the Americans and their allies are hostile invaders and “suggests transformation of the conflict is taking place”, he added.

Using the military to support a development strategy would help prolong the European presence, he suggested — “our European friends are less likely to leave us in the lurch”. If the US is left alone in Afghanistan, Brzezinski said, “that would probably spell the end of the Alliance.”