“We can no longer afford to do nothing. The appeal period is over and, as a lesson, Mahathir must be sued and pay damages,” he said in a Facebook post.

“I am willing to sue Mahathir myself.”

He said damages “to the tune of RM3 billion” was appropriate.

This comes after Mahathir abruptly walked out of an interview with the special task force reviewing the Batu Puteh, Middle Rocks and South Ledge sovereignty case at the Attorney-General’s Chambers (AGC) on Tuesday.

According to a report on Astro Awani, Mahathir did this in protest against former attorney-general Apandi Ali remaining as the task force chairman. He said Apandi’s appointment was a conflict of interest as he was the attorney-general in 2017.

Putrajaya had, on Feb 3, 2017, filed an application to review the ICJ’s decision on May 23, 2008 that Singapore had sovereignty over Batu Puteh.

However, in 2018, the Pakatan Harapan government under Mahathir withdrew the application before the case came up for hearing on June 11.