Vincenzo Nibali will head into the Alps with his hold on the yellow jersey intact after maintaining his two minutes 23 seconds lead over stage 12 to St Etienne yesterday.

Alexander Kristoff (Katusha) held off Peter Sagan (Cannondale) to clinch stage victory in a sprint finish after the peloton hauled back breakaway pair Simon Clarke (Orica Greenedge) and Cyril Gautier (Europcar) with 5km to spare.

Nibali was safely tucked in the peloton along with his nearest challengers Richie Porte (Team Sky) and Alejandro Valverde (Movistar), who retain second and third places respectively in the overall classification. Kristoff said: "I have been dreaming about this since I was a small child and to finally achieve it is nice.

"There will be champagne tonight, but tomorrow is a hard stage so we won't party much."

Today the Tour heads into the Alps for the first time this year with the 197.5 stage from St Etienne to Chamrousse, including the 1,154-metres Col de Palaquit.

And Porte, who assumed leadership of Team Sky following Chris Froome's injury-enforced withdrawal, is looking forward to the challenge of cementing his position among the leading group.

Porte said: "It's just nice to get through these stages and into the mountains."