Newcastle United are in advanced talks over the potential £340m takeover by Saudi Arabia's sovereign wealth fund.
Negotiations between the Arab state's Public Investment Fund (PIF) and Newcastle owner Mike Ashley have been in progress for several months.
The chances of an agreement are now "high" according to one source familiar with the discussions.
But they also warned that the talks were "complicated" and a deal could still collapse.
"Ashley does not need to sell, and he is unpredictable," said the source.
Businesswoman and financier Amanda Staveley is understood to have approached the Saudi Crown Prince Mohammed bin Salman about buying the Premier League club.
Staveley failed to purchase the club two years ago after Ashley said he wanted to bring 10 years of ownership to an end.
She is thought to want a 10% stake in the club if a deal can be agreed with PIF, which would be the majority partner.