Sky Sports sources understand Luka Modric has handed in an official transfer request at Tottenham.
Modric's future at White Hart Lane has been the subject of intense speculation all summer with Chelsea chasing the Croatian's signature.
Chelsea have already seen two bids of £22million and £27million for the 25-year-old rejected as they look to lure him to Stamford Bridge.
It was widely suggested Modric would hand in a transfer request in a bid to force a move away from Tottenham and it is understood he has made that request in writing.
Modric is currently with Spurs on their pre-season tour of South Africa, but he is desperate to make the move to West London.
Spurs boss Harry Redknapp and Spurs chairman Daniel Levy insist Modric is not for sale at any price, but they could find it difficult to keep the unsettled player now he has made his transfer request official.