Former premier Dr Mahathir Mohamad has been urged to declare his assets in Malaysia and abroad.

Pertubuhan Minda Sosial dan Prihatin (PMSP) president Ramesh Rao said this is to prove that Mahathir really is against corruption.

"Mahathir is very vocal about corruption. (He accused) Prime Minister Najib Abdul Razak of corruption.

"If you're really against corruption then walk the talk and declare your assets," Ramesh told reporters in Putrajaya today.