An Afghan forces air strike on a suspected Taliban gathering in the northern province of Kunduz on Monday caused dozens of casualties, including many civilians, officials said.

Abdul Hameed Hameedi, a local police official, said the strike in Dasht-i Archi district outside Kunduz city hit a gathering of Taliban fighters preparing an operation, killing 15 and wounding 10.

A representative from the Taliban leadership council based in the Pakistani city of Quetta was visiting when the air strike took place, he said.

He said there had also been civilian casualties but he had no details.

Local people said the strike had hit a mosque and that large numbers of civilians had been killed and wounded. Dasht-i Archi has been largely under the control of Taliban fighters and many details about the strike were unclear.

However health officials in Kunduz city said five dead and 40 wounded had been brought into city hospitals.

A statement from the Taliban said the strike killed 150 religious scholars and civilians and denied that any of its forces were present.

"There is no truth in this claim by the enemy that members of the Islamic Emirate were present at the ceremony or that members of the Taliban Council went there," the statement said.

Army Colonel Lisa Garcia, US Forces-Afghanistan spokesperson, said US forces had not carried out any attacks in the area.

"US Forces-Afghanistan did not conduct air strikes in Kunduz province today. Any claims to the contrary are baseless," she said in an e-mailed statement.

The incident nonetheless underlined one of the risks of the greater use of air power under the new US strategy announced last year to try to force the Taliban to the negotiating table.

Building up the fledgling Afghan air force (AAF) has been a major priority for the NATO-led Resolute Support training and advisory mission in Afghanistan and the AAF has had increasing success in supporting ground forces.

But civilian casualties caused by the air strikes have risked undermining public support for the campaign.

Recent figures from the United Nations have shown a rise in the number of civilian casualties caused by air strikes even while the total number of civilian casualties has declined.