ISLAMABAD - Another 500 US Marines are due to be deployed at an airfield south of Kandahar in Afghanistan, the Taliban's last citadel, "today or tomorrow", a coalition spokesman said Tuesday.

Some 500 Marines on Sunday and Monday secured the airstrip 20 kilometers (12 miles) south of Kandahar city and set the stage for what US President George W. Bush indicated may be the big push to drive the Taliban into a final retreat.

The international coalition against terrorism spokesman, Kenton Keith, told a news conference here the 1,000 Marines were an advance party and that they could well be joined by other coalition troops.

"That can't be ruled out," Keith said.

The first Marine units landed Sunday by helicopters from the amphibious assault ships USS Peleliu and USS Bataan. More Marines were flown in aboard C-130 transport planes after the airstrip was secured.

Asked whether the Marines were likely to lead an assault on Kandahar or instead play a supportive role for anti-Taliban Northern Alliance troops, Keith replied: "That will be up to the military commanders."

He added, however: "They (Marines) have a wide range of capabilities. They could be assigned many different roles."

As far as he was aware, the only action engaged in by the Marines since they arrived in Afghanistan was helping track, in their AH-1W Cobra helicopter gunships, an armored column near Kandahar Monday that was then attacked by a US Navy F-14 Tomcat fighter.

Asked when the military operation may be over in southern Afghanistan, Keith replied: "When the Taliban has been removed from power, when the al-Qaeda terrorist network has been destroyed and when Osama bin Laden has been brought to account."

He said that in addition to its military campaign, the international coalition against terrorism was also looking to Afghanistan's future, as evidenced by the political conference taking place in Bonn on Tuesday and a reconstruction conference currently underway in Islamabad.

"This is the day the Afghans begin to take their country back," Keith said.

"If the political process is successful, it will bring peace, stability and much-needed reconstruction to Afghanistan." - Nampa-AFP