Team Sky's Chris Froome is one of three riders who had been issued with a challenge by Tinkoff Saxo owner Oleg Tinkov to compete in all three of 2015's Grand Tours
Tinkov who has put up a €1m (£789,329) prize has also challenged Giro d'Italia winner Nairo Quintana and Tour de France champion Vincenzo Nibali to take on Alberton Contador.
Team Sky boss Sir David Brailsford for whom Froome rides said to the BBC: "Seeing the best riders slug it out across the season at key races is what everybody would want to see.
"From a performance point of view, it's quite a serious undertaking but, from a conceptual point of view, from a fan's point of view, from a sporting point of view, I think it's got a lot of merit."
No rider has won the Giro D'Italia, Tour De France and Vuelta a Espana in the same season aluth Marco Pantani won the Giro and Tour De France in 1998.