Trinidad and Tobago striker Dwight Yorke said concerns over the length of his contract with Sydney FC helped lead to his departure from Australia and the signing of a two-year deal Thursday with English League Championship club Sunderland.

Yorke, a 34-year-old former Manchester United star, was traded to Sunderland for 200,000 British pounds ($420,200 Cdn).

He said he was disappointed to leave Australia, but with no indication from Sydney FC of re-signing him beyond this season, it was in his best interests to return to England.

``If they did not really want me to go they would not have let me go, because they have the pulling power so to speak,'' Yorke said Friday.

Yorke's former Manchester United teammate Roy Keane has recently become manager at Sunderland.

``At the end of the day I have six months remaining on my contract (with Sydney) and then I am out of contract,'' Yorke said. ``There was no talk about me extending the contract and whether that was the case, it was not documented to me or my manager.

``I have a two-year deal in England, I had to think about it.''

Yorke joined Sydney FC in July 2005 and played 21 games in Australia's A-League. He scored seven goals and helped the club win the A-League's inaugural title.

Yorke also impressive during the World Cup as captain of the Caribbean side.

``Dwight Yorke has made an unbelievable contribution to Sydney FC and Australian football and we wish him nothing but luck in his new endeavours with Sunderland,'' Sydney FC chairman Walter Bugno said.