NATO airstrike kills five Afghan soldiers

The attack took place after a NATO-led International Security Assistance Force aircraft mistook Afghan National Army soldiers for Taliban insurgents during an operation in Ghazni province, southwest of Kabul, a spokesman for the Afghan defence ministry said.

"ISAF aircraft bombed and martyred five of our soldiers," spokesman Zaher Azimi said. "We condemn this incident and regret that this is not the first time such an incident has occurred. We hope it is the last time."

Civilian casualties and friendly fire deaths among Afghan security forces have been a frequent source of friction between President Hamid Karzai and western military forces during the nine-year war since the ousting of the Taliban in 2001.

But new U.S. and NATO forces commander General David Petraeus is considering a change to "courageous restraint" rules of engagement drawn up his predecessor General Stanley McChrystal in an effort to avoid civilian casualties, following complaints they are too restrictive.

An ISAF spokesman said the NATO commanders regretted the latest deaths.

(Reporting by Sayed Salahuddin; Editing by Rob Taylor and Alex Richardson)