The Appeal Court on Tuesday upheld yet another conviction against former opposition leader Sam Rainsy, this one for claiming Prime Minister Hun Sen bribed pro-government social media activist Thy Sovantha.

Rainsy made the accusation in France in January of last year, after messages allegedly between the premier and Sovantha, an opposition activist-turned-ruling party darling, were leaked to her Facebook page in November.

The messages dealt with undermining Rainsy’s now-dissolved Cambodia National Rescue Party, with the prime minister allegedly calling Sovantha “grandchild” and offering her $1 million to fund her activities.

Rainsy was found guilty of defamation in absentia in December, and ordered to pay $1 million to the prime minister.

Presiding Judge In Vannvibol said Rainsy’s post “affected the dignity and reputation of the prime minister locally and overseas”.

The case is one of at least eight currently hanging over the self-exiled political figure since a prior round of pardons in 2013. He has lived abroad to avoid imprisonment since 2015.

In an email, Rainsy derided the “Kangaroo Court” that he said ignored “irrefutable evidence”. Nevertheless, he pledged to appeal the decision to the Supreme Court, for another “opportunity to expose Hun Sen’s wrongdoings”.

He called for the court to investigate the more than 400 leaked messages which he claimed contained personal details that prove their authenticity.

A similar but separate lawsuit has been filed by Sovantha, who has claimed the messages were fabricated and her Facebook page was hacked.

Meanwhile, Rainsy went on an offensive of his own, tweeting demands for Hun Sen to step down or be removed.

Rainsy said the premier could negotiate a “safe exit” or “be forced to step down” by the people and armed forces.