Ghana have confirmed that the Chelsea midfielder Michael Essien has been ruled out of the World Cup after failing to recover from a knee injury.

A statement on the national team's official website said that a combination of medical experts from Chelsea and Ghana had come to the conclusion that the player would not be able to make a full recovery until the end of July.

"The Ghana Football Association wishes him a full recovery and a quick return to football action," read the statement.

Essien has struggled to return to full fitness since tearing his medial ligament in his left knee while training with Ghana prior to the Africa Cup of Nations in January.

Ghana begin their World Cup campaign in Group D against Serbia on 13 June.