Singer Michael Jackson may be too sick to travel to London to give evidence in a court case against him brought by a son of the king of Bahrain, his lawyer said.

Robert Englehart presented judge Nigel Sweeney with a medical report on Jackson's condition which was not read out in open court.

"On a best-case prognosis, it would be unwise for him to travel given what he's got now," he told the High Court, declining to elaborate on Jackson's condition.

Sheikh Abdullah bin Hamad al-Khalifa says Jackson reneged on a contract to record a new album and write an autobiography, and owed him $7 million.

Jackson wants to give evidence via video link from the west coast of the United States.

Sweeney said he planned to rule on whether Jackson would be allowed to do so or not on Thursday morning to give medical experts from both sides time to talk.

If he rules in favour of a video link, Jackson is expected to begin testifying on Monday or Tuesday.

Bankim Thanki, representing Shaikh Abdullah, said the medical evidence produced was "pretty unsubstantial" and that Jackson's illness, even if positively proven, would be easy to cope with.

"At the end of the day it all depends on the result of the pathology report," said Thanki, adding that the result should have been made available by now.

He added: "It's not the first time a sick note has been presented by Mr. Jackson ... My client isn't being hard-hearted or difficult, he is being rightly sceptical."         

According to the Press Association, Thanki earlier told the court how his client had "felt a strong sense of personal betrayal because this (Jackson) was someone he considered a close personal friend."    

He said Jackson had signed a contract for recording albums, writing an autobiography and staging shows in which it was agreed that $7 million would be deducted from Jackson's royalties to pay for expenses.

These included a bill for over $300,000 for motivational guru Tony Buzan who was flown to Bahrain to work with Jackson.

The star left Bahrain in May 2006 to go to Europe and Japan. "The last thing Sheikh Abdullah expected was that he was never coming back," Thanki said.

The following month, the sheikh was asked to sign a document releasing Jackson from his obligations under the contract but refused, the lawyer added.

Jackson spent time in Bahrain as a guest of the royal family following a 2005 trial at the end of which he was acquitted of child molestation charges.

In April 2006 a statement was released on behalf of Bahrain music label Two Seas Records announcing he would record a new album for release in 2007.

Jackson contests that there was no valid agreement and that the sheikh's case was based on "mistake, misrepresentation and undue influence".

In his pleaded defence, Jackson said the payments he received were "gifts" and that no project was ever finalised.

The case, expected to wind up by the end of the month, was adjourned until Thursday. - Reuters