Michael Jackson is thought to be too ill to testify in the case filed by Sheikh Abdulla bin Hama al-Khalifa.

According to lawyers, the pop star is unable to travel to London and they have requested if he could be allowed to give his testimony via video link from the US.

Mr Jackson is being sued over claims that he owes the sheik £4.7 million, after failing to fulfill an agreement to produce an album, stage play and autobiography.

Lawyer Robert Englehart said: "It would be unwise for him to travel, given what he's got now."

However he declined to give any more details of the medical complaint "for obvious reasons".

Khalifa, the second son of the king of Bahrain, claims the singer reneged on the deal, agreed while he was living in the small gulf state. Mr Jackson's lawyers argue that a contract never existed and the money was a gift.

Sheikh Abdulla's lawyer, Bankim Thanki, said: "It's fair to say my client felt a considerable sense of betrayal by someone he thought was a close friend."

Judge Nigel Sweeney will resolve the question of Jackson's fitness on Thursday.

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