Canada's MacDonald, Dettwiler and Associates Ltd. is to continue its unmanned aerial vehicle surveillance service in Afghanistan for Australian troops.

The new contract extends the UAV service until the end of this year, the company said. No details on the value of the contract were disclosed.

The Australian Department of Defense said it extended the operation of Heron UAVs in Afghanistan at the request of the International Security Assistance Force.

"The extension supports ISAF's requirement to maintain information, surveillance and reconnaissance capability during the traditional fighting season," it said.

"The current rotation of personnel, which was scheduled to return to Australia in mid-2014, will be extended for up to six weeks to allow an additional rotation of personnel to be prepared and deployed."

MDA has been supporting the Australian Forces in Afghanistan with its UAVs since early 2010.

The Heron is an Israeli made aircraft.