KABUL - Four NATO soldiers were killed in separate explosions in restive southern Afghanistan on Saturday, the military alliance confirmed in a press release on Sunday morning. ?

"Four International Security Assistance Force (ISAF) service members died following separate improvised explosive device (IED) attacks in southern Afghanistan yesterday," the NATO-led ISAF said in press release.

The brief release did not disclose the nationalities of the victims under the ISAF policy.

Troops mainly from the United States, Britain and Australia have been stationed in the southern region within the framework of ISAF to curb Taliban-linked insurgency there.

The Taliban stepped up their attacks on Afghan and NATO troops since a rebel offensive was launched earlier this month in the war-ravaged country.

Currently over 130,000 NATO-led ISAF troops with majority of them Americans have been serving in Afghanistan. A total of 160 foreign soldiers have been killed in the central Asian state so far this year.