Responding to Dr Mahathir Mohamad branding him as a liar, 1MDB president Arul Kanda said the authorities can decide on this.

"As a professional, I am fully accountable for my actions and answerable to the 1MDB board, and our shareholder the Ministry of Finance.

"In the current context, this also includes the auditor-general, Bank Negara and Public Accounts Committee (PAC).

"These are the lawful authorities to verify whether or not I have ever lied, as has been claimed, as they have access to all information," he added in a statement.

In a blog post yesterday, Mahathir rejected Arul's summary on where the company spent its RM41.8 billion loan.

He said this is because Arul has on various occasions been "caught lying" and therefore cannot inspire confidence.

Arul took over the helm of the ailing firm in January with the aim of reversing 1MDB's fortunes.

Prior to Mahathir jumping on the 1MDB bandwagon and calling for Prime Minister Najib Abdul Razak's head to roll over the matter, the opposition also raised a slew of questions regarding the firm's questionable transactions.

Meanwhile, Arul, in his statement today, said he wished to make it clear that his role in 1MDB "has been and will continue to be as a professional."

"I was initially appointed to conduct a strategic review of the company, and am now leading the implementation of a rationalisation plan for the business, as presented to cabinet on May 29," he added.