Fierce fighting between French soldiers of the NATO-led forces with about 100 attacking insurgents have left 10 French soldiers killed and 21 injured in Afghan central province of Kabul, the military alliance said Tuesday.

The clash erupted as a joint patrol involving French soldiers and Afghan security forces was attacked late Monday afternoon and continued into Tuesday, an officer from the media office of the NATO-led International Security Assistance Force (ISAF) read a statement to Xinhua via phone.

"The initial patrol was reinforced with quick reaction forces, close air support, and mobile medical teams," the statement said. "During the engagement a large number of insurgents were killed."

The statement did not mention if there were casualties on the Afghan forces.

This has been the deadliest single incident for Afghanistan- based international troops in months if not years and brought the figure of foreign soldiers deaths this year here much higher than 100.

The war-torn country during the past three months saw increasingly rampant militancy-related violence despite a 70,000- strong foreign troops are based here fighting Taliban-led insurgents.

Escalating Afghan war and violence has claimed over 3400 lives this year, according to reports.

The Taliban fighting the Afghan and foreign forces since being removed from power in 2001 has taken the responsibility. The outfit launched nearly daily ambush or explosion attacks on Afghan and foreign forces over the weeks and meanwhile reports of huge casualties inflicted on the insurgents also continued to surface.

Around 1,600 French soldiers are involved in the ISAF mission in Afghanistan and are mainly deployed in the central-eastern provinces of Kabul and Kapisa. Paris pledged in April to send additional 700 troops to eastern Afghanistan.

French President Nicolas Sarkozy said on Tuesday that he will fly later in the day to Afghanistan soon, reports reaching here said, after the French troops suffered the worst losses in overseas battlefields in years.

In a related development, militants have planned three attempted attacks on a U.S. military base in eastern Afghan province of Khost since Monday, with an initial explosion one which killed 10 Afghans outside the base Monday.

(Xinhua News Agency August 19, 2008)