Bee Taechaubol has confirmed he reached a deal to buy 48% of the AC Milan football club for €480 million (18.48 billion baht).
The property tycoon posted on Instagram a photo of him shaking hands with former Italian Prime Minister Silvio Berlusconi late on Sunday, describing it: "A great honor to complete the AC Mlian Agreement with former Italian president Berlusconi, a phenomenal leader".
A spokesman for Fininvest, the holding company which owns the Serie A club, said on Sunday Mr Berlusconi had signed a pre-sale agreement to sell 48% of his AC Milan football club to a group led by Mr Bee by the end of September.
"A deadline of September 30 has been set for transfer of the stake and payment of the €480 million by September 30," the Fininvest spokesman told Reuters.
AC Milan is owned by Fininvest, Mr Berlusconi's family holding company which also controls Italian TV broadcaster Mediaset and publisher Mondadori.
The deal was signed by Fininvest and Mr Bee and approved by Mr Berlusconi, the spokesman said.
Both were reported to have been in talks since early June.
Mr Berlusconi will retain control and his post as president of the club, according to ESPN.
Me Bee also gave an insight into his plans for the club in an interview with Mediaset.
"We signed an agreement that allows our investors to start working very soon for the club," he said.
"We agree we want to grow Milan even more around the world. I'll be seen most often at San Siro [a football stadium in Milan], in the role of supporter with President Berlusconi.
"To win together? Yes, of course," he said.
Under Berlusconi’s 29-year tenure, AC Milan has won seven European championships and remains one of Italy's most glamorous clubs but it has lost some of its shine in recent years. It won the most recent of its 18 Serie A championships in 2011, racked up debts of €250 million and lost €91 million last year.
Earlier this year, Mr Bee earlier said he wanted a controlling stake in the club. Mr Berlusconi also told Italian media he intended to keep his 51% holding.
Mr Berlusconi, whose political fortunes have faded in recent years, has previously said that one family alone was not able to meet the challenge posed by the rising investments required to run a football club.
When the deal closes, Mr Bee will be the latest in a string of foreign businessmen who have snapped up some of Europe's most glamorous football clubs in recent years, Reuters said.
In 2013, a group of Indonesian investors bought Inter Milan, ending the long reign of the Moratti family over the team.