Frank Lampard and John Terry will be out of England's Euro 2012 qualifiers against Bulgaria and Switzerland next month due to injury.

Lampard will undergo a hernia operation next week and Terry had glute and hamstring problems, revealed Chelsea coach Carlo Ancelotti on Saturday.

"John has spoken personally to the England management team, and Chelsea and England medical staff have also been in touch," The club said in a statement. "All are agreed that John's injuries, that he has carried since pre-season, would benefit from a period of rest and rehabilitation."

Strikers Peter Crouch and Bobby Zamora may also miss the qualifiers as they both sustained injuries in action for their clubs on Saturday.