The US airstrike that killed 22 at a medical clinic in northern Afghanistan over the weekend was requested by Afghan forces who reported being under Taliban fire, the top commander of American and coalition forces said Monday.

General John F. Campbell said the airstrike, whose victims included three medical staff from the French charity Médecins Sans Frontières (MSF), was not sought by US forces, contrary to the Pentagon’s initial statement.

"We have now learned that on Oct. 3, Afghan forces advised that they were taking fire from enemy positions and asked for air support from US forces," Campbell said.

"An airstrike was then called to eliminate the Taliban threat and several civilians were accidentally struck. This is different from the initial reports which indicated that US forces were threatened and that the airstrike was called on their behalf," he added.

Campbell, who was speaking at a hastily-arranged conference at the Pentagon, also expressed his “deepest condolences” to the civilians killed in Kunduz by US aircraft.

The revised account does not clarify whether the clinic was targeted in error or whether other mistakes may have been made by US forces.

"If errors were committed we will acknowledge them," Campbell said.

FRANCE 24’s Washington correspondent Philip Crowther said the Pentagon would eventually have to reveal “whose initials or on the order to launch that airstrike in the first case, who gave that order on the US side”.

Campbell declined to provide more details, saying a military probe is ongoing and that Brigadier General Richard Kim was the senior investigator looking into the affair.

(FRANCE 24 with AP, REUTERS)