Former prime minister Dr Mahathir Mohamad has denied he approved a RM507.77 million contract for Malaysian Maritime and Dredging Corporation Sdn Bhd (MMDC) without the cabinet's approval, as revealed by Auditor-General Report 2015 (Series 2).

"No, that's invention," Mahathir told reporters when met at Dataran Merdeka last night.

"They should show proof," he said curtly before leaving.