Six soldiers of the NATO-led International Security Assistance Force (ISAF) were killed in Taliban attack on Sunday, a statement of the alliance released?in Kabul?said.

"Six International Security Assistance Force service members died following an insurgent attack in southern Afghanistan today," the statement said.

However, it did not identify the nationalities of the victims, saying it is ISAF policy to defer casualty identification procedures to the relevant national authorities.

Troops mostly from the United States, Britain, Australia and Canada have been stationed in the restive southern region to stabilize security there.

This is the largest fatalities inflicted on NATO troops in a single day bringing the number of casualties to 22 since beginning December.

More than 680 NATO soldiers with majority of them Americans have been killed since January this year in Afghanistan.