The mountaineers had "died of exhaustion", the Haute-Savoie prefecture told AFP, adding that rescuers who finally reached the site found the two Koreans first, close by the two Italians.

A helicopter from the PGHM mountain police based in Annecy was able to land at around 1:30 pm (1130 GMT) and found the bodies between 100 and 200 metres (330-660 feet) from the summit.

"The bodies have been brought down" from the mountain and "the families informed", the PGHM's Chamonix branch said.

A group of Italian mountain rescuers had reached the summit on foot after setting off in the morning but did not spot the bodies, the police added.

Police were alerted late on Saturday about "three missing climbing parties near the summit of Mont Blanc in very poor weather conditions".

The parties had set off "without guides", the prefecture said.

An intensive rescue effort retrieved two Koreans, who were alive, at 4,100 metres (13,450 feet) on Sunday morning.

But the weather later worsened, leaving rescuers unable to keep up the search for those still out on the mountain in subsequent days.

As late as Tuesday morning, a search helicopter had turned back from Mont Blanc as it could not find a way through clouds.

One senior PHGM commander told regional daily Le Dauphine Libere that they had briefly reached the Italians by phone and gleaned their location 4,600 metres up on Mont Blanc's north face, but that the connection had cut out.

At 4,809 metres, Mont Blanc is western Europe's highest peak and very popular with climbers from all over the world.