Nibali signed his new contract during a trip to Kazakhstan with several teammates, where he is due to meet Kazakhstan President Nursultan Nazarbayev.
Cyclingnews understands that Nibali will earn close to four million Euro per season, making him one of the best paid riders in the peloton.
Astana team manager Alexander Vinokurov and Vice President of Kazakhstan's Cycling Federation Darkhan Amanovich Kaletaev announced Nibali's new contract at a press conference in Astana, confirming that Nibali will target the Vuelta a Espana and the world road race championships in Florence in the second half of the 2013 season and then target the Tour de France in 2014.
"We are very pleased to prolong our contract with Vincenzo Nibali today in Astana, and look forward to supporting him at the Vuelta a Espana in August and at the World Championships in Firenze at the end of September," said Vinokurov in a press release from the team.
"To have a great champion on Astana Pro Team ahead of Expo 2017 in Kazakhstan's capital will help to broadcast around the globe that our cycling federation has world-class talent to go with its world-class ambitions. Next year we will look to bring Vincenzo to the 2014 Tour de France."
Nibali will not ride this year's Tour de France and is expected to return to racing at the Tour of Poland in late July.