AUSTRALIA has the green light to deport thousands of Afghan asylum seekers after reaching a historic agreement with the Afghan government.

The Immigration Minister, Chris Bowen, signed a memorandum of understanding with the Afghan Refugee Minister, Jamaher Anwary, and the United Nations High Commissioner for Refugees in Sydney yesterday.

"It is important that Afghans not owed protection are returned to Afghanistan" ... Immigration Minister, Chris Bowen.

It enables the forced return of Afghans whose bids for asylum fail. The move is alarming security experts and refugee advocates.

Mr Bowen said it would deter Afghans considering travelling to Australia. ''Never, all through the Howard years, never before today, has there been an involuntary return from Australia to Afghanistan,'' he said.