The Supreme Court on Monday upheld the five-year prison sentence handed to former Cambodia National Rescue Party president Sam Rainsy for his involvement in the dissemination of forged Cambodia-Vietnam border documents.

“The Supreme Court decided to uphold the Appeal Court’s decision. As for the grounds of the decision, I cannot explain. All I can say is that the Supreme Court upheld the Appeal Court’s verdict,” said Ouk Kimseth, its deputy prosecutor.

Last week, the court heard an appeal by Rainsy, who, along with his two Facebook administrators, was convicted in absentia in December 2016 and sentenced to five years’ imprisonment on charges of “being an accomplice in faking public documents and incitement”.

Rainsy and the two administrators – Sambath Satya and Ueng Chong Leang, both in their 20s – fled to France.

This case originated from a video clip that was posted on Rainsy’s Facebook page in August 2015.

In the over 10-minute video clip, Hong Sok Hour, then a Sam Rainsy Party senator, presented a “fake” version of a 1979 treaty that purported to dissolve the border between Cambodia and Vietnam.

Sam Sokong, Sam Rainsy’s defence lawyer, last week argued that Rainsy could not be responsible for the Facebook post because he was out of the country at the time and did not return until five days later.

Sokong did not attend the verdict announcement and said he declines to proffer an opinion on the decision.

“The decision is final, so I have no comment,” Sokong said.

Sok Hour was sentenced to seven years in prison in November 2016. However, he was pardoned last year after apologising to Prime Minister Hun Sen.