Manchester City owner Sheikh Mansour always spoke “very highly” of a businesswoman involved in brokering a deal relating to the sale of Newcastle United, a High Court judge has been told.

A former adviser to the Emirati businessman told Mr Justice Waksman that Amanda Staveley was regarded as “someone of high standing”.

Ali Alatieh Jassim was giving evidence at a High Court trial in London involving Ms Staveley and Barclays, on Wednesday.

“Sheikh Mansour always spoke very highly of Ms Staveley and referred to her as a smart businesswoman,” said Mr Jassim.

“He saw Ms Staveley as being somebody of high-standing, a well-known businesswoman rather than just a broker trying to get a deal done.”

Mr Jassim had told the judge that he had first met Ms Staveley 13 years ago when Sheikh Mansour wastaking control of Manchester City.

Mr Jassim said Ms Staveley, who was representing the then Manchester City owner Thaksin Shinawatra, had a “growing reputation” in the Gulf as a “notable deal-maker”.

He said he recalled being impressed with her ability to get the Manchester City deal “over the line” as “smoothly as she did”.

Ms Staveley has made complaints about the behaviour of Barclays’ bosses when negotiating investment deals during the 2008 financial crisis.

She says Barclays agreed to provide an unsecured £2 billion loan to Qatari investors.

But she says that loan was “concealed” from the market, shareholders and from PCP Capital Partners, a private equity firm she runs.

PCP is suing the bank and wants £1.6 billion in damages.

Ms Staveley, who in recent months has been involved in brokering a deal which could see a Saudi consortium take control of Newcastle United, says PCP introduced Sheikh Mansour to Barclays and he “subscribed” to invest £3.25 billion.

She says PCP is owed money for the work it did.

Barclays disputes PCP’s claim and says it is made “of sand”.

Mr Justice Waksman began overseeing a trial in London more than two weeks ago.

The trial, which is due run into August, has adjourned.

It is scheduled to resume on Thursday July 2 when lawyers representing Barclays are due to begin calling witnesses.