Newcastle United owner and Sports Direct boss Mike Ashley has been accused of reneging on a £15 million deal he made with a finance expert during a night of heavy drinking in a pub.

Investment banker Jeffrey Blue says Mr Ashley promised to pay him £15 million if he used his expertise to double Sports Direct's share price to £8 a share, during an evening at a London pub four years ago.

He says Mr Ashley paid only £1 million and he wants £14 million damages.

Mr Ashley denies the claim and says Mr Blue is talking ''nonsense''.

The two men are fighting at a High Court trial in London.

A judge began overseeing the trial last week and had heard from Mr Blue and Mr Ashley.

Lawyers are outlining closing legal arguments to Mr Justice Leggatt.

The judge is expected to deliver a ruling later in the year.

A barrister representing Mr Blue on Wednesday told the judge that Mr Ashley had "reneged".