Chelsea have said Eden Hazard's ankle surgery was a success and expect the midfielder to return to training in three months meaning he will almost certainly miss the start of the Premier League season on August 12.

Belgium midfielder Hazard sustained a fracture in his right ankle training, and will miss this week's international matches.

"Eden Hazard successfully underwent surgery today after sustaining a fracture to his right ankle while training with the Belgian national team. He is expected to return to training in approximately three months," said the Premier League champions in a statement.

Hazard, who scored 16 goals and provided five assists to help Chelsea win the Premier League, is ruled out of his country's friendly against Czech Republic on Monday and a World Cup qualifier against Estonia on June 9.

"Eden Hazard will miss both games with Belgium this week due to an ankle injury which he suffered during this afternoon's training session," Belgium team media officer Stefan Van Loock said in a statement.

"Medical imaging showed that the injury... is an ankle fracture (right ankle)," he added without giving a timeline for the 26-year-old's recovery.

Belgium have won four of five 2018 World Cup qualifying matches to lead UEFA Group H on 13 points, two points ahead of second-placed Greece.