TOKYO -- Former Olympic champion Ryu Seung-min, now president of the South Korean table tennis association, has tested positive for COVID-19 upon arrival at Narita International Airport for the upcoming Tokyo 2020 Olympic Games.

Ryu, who beat China's Wang Hao to claim the Olympic singles title in Athens 2004, confirmed the news on social media late on Saturday night but deleted his post the following morning.

"It is with great disappointment that I have to inform you that I will not be able to attend the Olympic Games Tokyo 2020 at present," the 38-year-old had written on his Facebook account.

"Despite having been fully vaccinated with two doses, and I got the 2 times negative result in COVID-19 test and having taken my departure tests when leaving [South] Korea, however I tested positive for COVID-19 upon arrival at Narita airport this afternoon," it read.

He was immediately brought to the official isolation facility and is waiting for official clearance.

Ryu said on Facebook, "I am completely asymptomatic which probably has to do with the fact that I am vaccinated."

A four-time Olympian and a member of the Athletes Commission and the IOC's Olympic Education Commission, Ryu was supposed to attend the IOC session on July 20-21.

"I apologize to the organizing committee, our hosts here in Japan, and the IOC for the inconvenience I have caused. I want to thank everyone for their diligent work," Ryu said.

"My case is just another proof that the system put in place to protect all of us is effective," he added.

South Korea's table tennis team, which is not traveling alongside with Ryu, is set to depart from Seoul on Monday for the competition which opens at the Tokyo Metropolitan Gymnasium on July 24.