LONDON (AFP) - Romelu Lukaku has said he may have to leave Chelsea if the English Premier League giants sign Diego Costa.

The 21-year-old Lukaku has spent the past two seasons on loan at English top-flight rivals West Bromwich Albion and Everton, with Jose Mourinho the latest Chelsea boss seemingly happy to do without the Belgian striker.

"You know Chelsea: every year they buy a new top striker," Lukaku was quoted as saying by several British newspapers on Saturday.

Lukaku, who scored 16 goals for Everton last season, added: "I remember me coming into the dressing room last year and seeing Samuel Eto'o and Demba Ba and going: 'Whoa! What's happening here?'

"But no problem. Many clubs are interested in me.

"At this stage I have to look to myself. I have to play a good World Cup. That's very interesting for all the players looking for a transfer, and I must be one of them. Chelsea know my point of view."