KHOST, July 1: Invading US and Nato troops killed dozens of Afghan militants on the Afghanistan-Pakistan border, officials said on Tuesday, after foreign forces suffered their deadliest month since the fall of the Taliban.

US-led helicopters and bombers killed 33 insurgents in the eastern Khost province late Monday, while Nato soldiers in the same area cooperated with Pakistani troops across the frontier to kill several more militants, they said.

But the violence came as the invading troops passed a grim milestone, with the 49 soldiers who died in June making it their bloodiest month yet in Afghanistan and worse than Iraq for the second month in a row.

The Taliban have dramatically stepped up their attacks against US-led invading troops after being ousted from government in late 2001.In Khost, the US-led coalition said it launched air strikes after spotting Afghan rebels armed with rockets and heavy weapons massing about eight kilometres (five miles) from the Pakistan border.

“After positively identifying the militants, coalition forces engaged with them using attack helicopters and close air support bombers, killing approximately 33 militants,” spokesman Lieutenant Nathan Perry told AFP.

Separately, an outpost of Nato’s International Security and Assistance Force (Isaf) in troubled Khost came under attack late Monday from Afghan rebels using rockets and small-arms, an ISAF statement said.

Isaf, co-ordinating with the Pakistan military, responded with air strikes, artillery and rocket fire, causing the militants to flee into Pakistan, it said.

The statement said a number of Taliban were killed but did not specify how many.

The joint operation comes despite growing tensions between Pakistan and western nations with troops in Afghanistan, and less than a month after US forces killed 11 Pakistani troops in an air strike.—AFP