England striker Jermain Defoe can leave Sunderland on a free transfer if they are relegated from the Premier League, Sportsmail can confirm.

The clause in the 34-year-old's contract is sure to spark a scramble for his signature among top-flight clubs.

Bournemouth and West Ham have a long-standing interest in their former player but his return to the England set-up could alert others in the top half of the Premier League.

Sunderland striker Jermain Defoe will be able to leave the club on a free if they are relegated

The Black Cats are currently bottom of the table and seven points adrift of safety despite Defoe scoring 14 times in the league this season.

And he will be free to quit the Wearsiders should David Moyes' side succumb to the increasing inevitability of relegation to the Championship.

Sunderland gambled on not selling Defoe in the January transfer window - there was a £6m bid from West Ham - and they are still hoping that his goals can see them pull off another great escape.

The striker has scored 14 goals for the Black Cats this season, but they are seven points adrift

But the club's hierarchy know they will get nothing back for their star player should they fail to beat the drop. Defoe has already hinted that he will be forced to leave the club if they go down.

After making a scoring return to the international scene during Sunday's 2-0 victory over Lithuania, the forward was encouraged by the comments of manager Gareth Southgate about his chances of staying in the squad for Russia 2018.

Defoe will not want to jeopardise that opportunity and the free-transfer clause at least avoids a situation where he has to demand a move away from the Stadium of Light, preserving his popularity with supporters.