American Brandon McNulty took the overall lead of cycling's Paris-Nice in the scenic low Alps on Friday as his escape partner Mattias Skjelmose won hilly stage six.

A youthful trio of Team UAE's McNulty, another American Matteo Jorgenson of Visma and Skjelmose, escaped from the elite riders and worked hard together to achieve a surprise victory.

"That was a really hard final 50km, and I never expected to take the yellow jersey," said McNulty. "But it was like we were teammates."

Pre-race favourite Remco Evenepoel led the chasing group across the line 52sec later and remains in fifth.

Known as the 'Race to the Sun' as it leaves the cooler north towards the Riviera town of Nice 139 riders embarked from Sisteron for the 198km run over five hills of around 1000m altitude with around 30km of climbing.

But the action heated up on the final downhill dash with the three escapees in daredevil mode as they extended their lead racing to La Colle sur Loup.

Danish champion Skjelmose made his sprint from 400m out with McNulty edging his compatriot Jorgenson.

"I feel better than when I won the Tour de Suisse last year and I think I'm in a good place right now," said the Dane.

Overall leader McNulty faces two tough mountain stages over the weekend, but goes into it as the man to beat leading Jorgenson by 23sec.

Big guns Evenepoel and Egan Bernal are at 1min 03sec and 1min 14sec respectively.

Looking forward to the weekend, the weather is set to take a bad turn for the penultimate stage on Saturday with snow forecast at the finish line in Auron.

Race organisers are still waiting for the latest forecasts before possibly proposing an alternative arrival destination.