KUALA LUMPUR – Tun Dr Mahathir Mohamad’s two eldest sons said Malaysia’s anti-graft agency ordered them to assist with an investigation into their father, revealing for the first time that a months-long probe is targeting the 98-year-old former premier.

“My father is the primary suspect,” Tan Sri Mokhzani Mahathir, 63, said in a March 23 interview in Kuala Lumpur. “We are witnesses to whatever it is that they are investigating.”

In January, the Malaysian Anti-Corruption Commission (MACC) ordered Mr Mokhzani and his elder brother Mirzan, 65, to declare their assets dating back to 1981, the year Dr Mahathir became premier.

The orders are part of investigations into offshore business records revealed by a journalism consortium, the MACC said at the time, without mentioning that the main target was Dr Mahathir.

A spokesperson for the MACC said the agency was unable to comment on or confirm Mr Mokhzani’s comments.

Dr Mahathir’s office has not responded to a request for comment.

The brothers are assisting in the investigation, but the task is onerous and taking time, they said in the interview, which Mr Mirzan joined by video call.

Both have received two extensions of the original February deadlines for compliance.

The MACC has not provided the brothers with any details of the investigation into Dr Mahathir, according to Mr Mokhzani.

“We did ask, ‘What is the investigation on my father about?’ and they were not able to furnish us with that information,” he said. “Can you imagine you are being asked to provide information to be used to prosecute your parent?”

Datuk Seri Anwar Ibrahim, who finally became prime minister in 2022 after falling short of the top job for decades, is a former protege of Dr Mahathir who was seen as his successor, but later fell out with him.

Dr Mahathir dismissed Mr Anwar from all government posts in 1998, and Mr Anwar was later imprisoned on corruption and sodomy charges, which he denied.

The developments shocked the nation and turned Mr Anwar into an opposition figure who pushed for democratic reforms. 

Mr Anwar’s government faced criticism from the opposition and civil society groups in 2023 after the attorney-general withdrew 47 criminal charges against Deputy Prime Minister Ahmad Zahid Hamidi, a key ally in the government.

Mr Anwar has denied interfering in the case or in the MACC’s investigations.

Mr Anwar’s press office declined to comment. 

Dr Mahathir, who led Malaysia for nearly a quarter century in two different stints, said at a media briefing in January – conducted before Mr Mokhzani was ordered to declare his assets – that the probe involving his son Mirzan was politically motivated.

Just days after he spoke to reporters, Dr Mahathir was admitted to the National Heart Institute in Kuala Lumpur, where he was hospitalised for 53 days. He was discharged last week.

Dr Mahathir’s sons said they are working with company secretaries and accountants to file the asset declarations. 

“This is a near impossible task, to go back all that way,” Mr Mokhzani said, adding that he was still a student in Britain in 1981.

“We can’t remember exactly how things were back then,” he said, adding that everything was in the form of physical records and not digitalised.

The political wrangling has had a limited impact on markets. 

Malaysia’s ringgit is Asia’s top performer in March, after the central bank urged government-linked companies and funds to repatriate their overseas income and convert it to the local currency.

This helped to turn around the performance of the currency, which was the worst performer in South-east Asia after the Thai baht in the first two months of 2024, mainly weighed down by the weaker outlook of China, Malaysia’s main trading partner, and from a wide policy rate differential with the Fed.

Although Malaysia’s benchmark stock index has fallen in five of the past six years, the weak performance has abated to an extent in 2024.

The KLCI index is up more than 5 per cent, as the authorities attempt to stabilise the ringgit.

MACC is also investigating Daim Zainuddin, a former finance minister and close aide to Dr Mahathir.

Both Daim and his wife Na’imah Abdul Khalid were charged in January for not declaring their assets, which include the 60-storey Ilham Tower building in Kuala Lumpur that the agency seized in December.

They both pleaded not guilty.

In response to questions for this story, Na’imah said she and her husband did not have anything further to add. 

Dr Mahathir and Mr Anwar reunited in the 2018 election to oust former premier Najib Razak in the wake of the multibillion-dollar 1Malaysia Development Berhad scandal.

Dr Mahathir became prime minister for the second time, and made an agreement to hand over the premiership to Mr Anwar at an unspecified date.

But squabbling within the coalition, including over when Dr Mahathir would step aside as prime minister, helped bring down the administration in 2020.

In May 2023, Dr Mahathir filed a RM150 million (S$42.7 million) defamation suit against Mr Anwar, alleging the current premier had accused him of enriching himself and his family members during his time as prime minister.

The suit came after Mr Anwar said that a person who has been in power twice was taking everything for his family.

Mr Anwar has filed a statement of defence and is seeking to strike out Dr Mahathir’s legal suit.

“Anwar has said that I have stolen government money,” Dr Mahathir said at a media conference on Jan 22. “As far as I know, I haven’t stolen a single cent.” BLOOMBERG