Singapore on Friday ordered Facebook, TikTok, and other social media giants to block accounts belonging to a self-exiled Chinese businessman who alleged the city-state was "in the pocket" of a foreign country.

US-based Guo Wengui, a fierce critic of the Chinese Communist Party and ally of right-wing figure Steve Bannon, was found guilty Tuesday of defrauding customers of more than $1 billion in a New York federal court. He faces decades in prison.

On Friday, Singapore's Ministry of Home Affairs (MHA) said it had used a law against foreign interference to order Facebook, Instagram, YouTube, TikTok and X to block access to 95 accounts belonging to the billionaire and his affiliated organizations.

Among Guo's allegations was that a "foreign actor" -- identified as China in local media -- was behind the selection of new Singapore Prime Minister Lawrence Wong, who took over from Lee Hsien Loong in April.

The FBI arrested Guo in March 2023 at his luxury Manhattan apartment, accusing him of using his online fame to bilk thousands of investors.

The MHA said Guo and his affiliate organizations coordinated social media posts between April and May of this year containing "narratives which alleged that Singapore is in the pocket of a foreign actor".

The posts also alleged that the "foreign actor" was "behind the scenes in the selection of Singapore's fourth-generation leader", a reference to Prime Minister Wong's ascension.

The MHA cited a 2021 study by social media analytics firm Graphika that said Guo was "at the centre of a vast network of interrelated media entities and social media accounts that disseminate disinformation across multiple platforms".

The timing of the April-May social media posts indicated "deliberate planning" and gave reason to believe that Guo's network could "potentially harness the 95 accounts to mount hostile information campaigns which are targeted directly at Singapore," the MHA added.