Nairo Quintana says he has focused his training ahead of the Tour de France in an attempt to hold off yellow jersey rival Chris Froome's potent attacking climbs.

Movistar's Quintana and Team Sky leader Froome are hot favourites for this year's race - Froome aiming for his third Tour title, with Quintana hoping to back up his two white jerseys by securing a first overall success.

Quintana also won the polka-dot jersey in 2013 and highlighted the mountains as crucial in his bid to best the Kenya-born Brit.

The Colombian told a news conference: "I have been doing some training to try to stop strong attacks. 

"We all know that when Froome makes one of those strong attacks, it is really difficult to follow him. 

"We have seen in last two editions that those two attacks from him, the one that better reacted was me. But I am still preparing and I hope this year that I can respond to his attacks.

"There are some stages that are key for the General Classification, probably the time trials, taking into account that one of them is very close to the Mont Ventoux, and think those couple of days could be very interesting. 

"And then, obviously the last week is full of mountains and there we will see huge differences."

Quintana is looking for a second Grand Tour title, following his Giro d'Italia triumph two years ago.

He added: "I don't know if the dream is stronger, or I am more calm and with more will. 

"I am at a good level and hope to be at the right level for my rivals. I have been in one race before the Tour, in which the goal was to evaluate in which form I was, and the result was very positive. 

"I hope that I don't have any issue or complication in the first stages of the Tour."