As foreshadowed last year, Australian Greens Leader Senator Bob Brown will today move for the first Senate debate of the year to call on the Government to begin safely and securely withdrawing Australian combat troops from Afghanistan.

Last year the Government and Coalition voted down a Greens' motion to debate the ongoing deployment of troops to Afghanistan.

Following the London conference on Afghanistan, Senator Bob Brown said it was urgent the Parliament debate Australia's ongoing combat role in the region.

"Eleven Australian defence force personnel have been killed to date, and thousands of Afghani civilians have died," said Senator Brown.

"Despite this Foreign Minister Stephen Smith is yet to publicly acknowledge any plans or conditions for withdrawal from Afghanistan.

"The human and financial cost of maintaining Australian troops in Afghanistan must be debated."