Prime Minister Dr Mahathir Mohamad has demanded proof from those who have accused him of plotting to prevent Anwar Ibrahim from succeeding him.

With his trademark sarcasm, the 93-year-old politician described it as a “very nice allegation”.

“I think the person should give proof to it. I have never even talked to anybody else about this thing.

"I stayed away. I have no business to do anything with the internal affairs of other parties," he told a press conference in Putrajaya this evening.

This is the second time Mahathir has been confronted with questions of a plot against Anwar in the past two decades.

The first was in 1998 during Mahathir's initial tenure as premier when he sacked Anwar as his deputy. The latter accused his former boss and those close to him of a political conspiracy based on trumped-up allegations.

In the latest round, PKR lawmaker Abdullah Sani Abdul Hamid claimed that Mahathir and his trusted advisor Daim Zainuddin, who was also part of the 1998 episode, were colluding with PKR deputy president Azmin Ali against Anwar.

Abdullah is aligned to former Pandan MP Rafizi Ramli, who is contesting against Azmin for the PKR number two post.