Foreign Minister Alain Juppe said Tuesday that France would not give in to "panic" and pull its troops out of Afghanistan this year after four of its soldiers were killed there last week.

"When I hear talk of an immediate withdrawal, such as at the end of 2012, I am not sure that this has been thought through and studied," he told the French parliament.

Juppe was responding to a call from Socialist former prime minister Laurent Fabius for French troops to be brought home by the end of the year.

"We must not give in to panic, we must not confuse an orderly withdrawal with a rushed withdrawal," he said.

The four unarmed soldiers were killed on Friday at a base in eastern Afghanistan in an attack that left 15 other French troops wounded, eight of them seriously.

French President Nicolas Sarkozy reacted angrily, threatening to pull his forces out of Afghanistan ahead of the 2014 deadline for all US-led coalition combat troops and dispatched Defence Minister Gerard Longuet to Kabul.

Longuet said in the Afghan capital that he was told the killer was a Taliban infiltrator in the ranks of the Afghan army.

But security sources say the man arrested for the shooting has confessed to interrogators that he did it because of a recent video showing US Marines urinating on the bodies of dead Taliban fighters.