BERLIN (AFP) - Werder Bremen chairman Jurgen L Born insists Brazilian midfielder Diego will only leave the Bundesliga club over his "dead body" after reports both Real Madrid and Chelsea are interested in signing the play-maker.

"If somebody wants to buy Diego, he must murder me first. Diego will leave Werder only over my dead body," Born was reported as saying on German agency SID, quoting Spanish media reports.

Diego, 23, is one of the biggest stars of the Bundesliga and has attracted attention from Europe's top sides, but is contracted to Bremen until 2011.

Werder's Germany midfielder Tim Borowski will join Bayern Munich this summer and Born says there is no way he will let Diego follow him out the door.

"No one has rang me from Madrid - neither regarding Diego nor any other Werder players.

"Diego is not for sale. He has a contract with us until 2011 and is the most important player in our team."

With 26 caps for Brazil and three goals, Diego says he has spoken to international team-mate Robinho about Real Madrid, but has had no direct contact with the club.