"I didn't know he was corrupt" - that was former premier Dr Mahathir Mohamad's response when asked as to why he appointed Zulkipli Mat Noor as the Anti-Corruption Agency chief in 2001.

"They never told me that he was corrupt," he said.

Mahathir said from the reports given to him, he was under the impression that Zulkipli was clean and the right person to helm the agency.

"At the time when his name was given to me, everything was cleared," he said at a press conference at his Perdana Leadership Foundation office in Putrajaya.

The ACA falls under the jurisdiction of the Prime Minister's Department with the prime minister the person responsible in appointing the head of the agency.

"You can go and see his file. It must be somewhere... (see if) they put in that file that 'this man is corrupt so please appoint him as the ACA head'. You think I will appoint him if that was the kind of report? I don't know (then). Now I know. They didn't tell me," added Mahathir.

Apart from the first appointment that was made in 2001, Mahathir had also extended Zulkipli's tenure by offering him a one-year contract after the ACA chief reached his retirement in 2004. Subsequently, the present Prime Minister Abdullah Ahmad Badawi extended the contract on two occasions.

Zulkipli has come under intense fire in the past two weeks after he was accused by a former high-ranking ACA official, Mohamad Ramli Abdul Manan, of amassing properties and wealth beyond his means.

The whistleblower, who is a former Sabah ACA chief, also claimed he was cold-storaged in the agency upon an instruction from Mahathir for probing the corruption case involving former minister Kasitah Gaddam.

Abdullah under fire

Mahathir however dismissed Ramli's claim and asked him to back his allegations with evidence.

Ramli has also alleged that all high-profile corruption cases required Mahathir's 'permission' to be brought to court.

To this, the outspoken ex-premier snapped: "Nonsense, you mean I spend my time for doing all that work?"

Mahathir's sarcastic attacks also extended to Abdullah whom he claimed to have a hand in the recent revelations of corruption cases, apparently all from the time he was the premier.

He said that his name was being dragged through the mud in all these cases - as part of a concerted effort by Abdullah - to "blacken my name".

"I think there seem to be some plan or instruction to make my name as dirty as possible," he said, and confirmed he was referring to Abdullah when asked by reporters later.

He continued in the same sarcastic vein when asked about the on-going corruption probe against his former aide-turned-foe, Deputy Internal Security Minister Mohd Johari Baharum.

Johari has been accused of receiving more than RM5.5 million in freeing three underworld suspects who were held under the Emergency Ordinance, which allows detention without trial.

'Wanna bet'

As soon as Johari's name was raised, the ex-premier interjected and said to the laughter of the reporters: "Datuk Johari is cleared, he has not taken even one cent. You can be sure that will be the finding."

When he was asked whether he was providing a serious answer, Mahathir replied: "I am serious, he is completely clear. He cannot be found guilty of such a thing, it is impossible... you want to take a bet? Anybody want to take a bet?"

Previously Mahathir had accused Johari of manipulating the Kubang Pasu Umno divisional election last year, causing in Mahathir to suffer a humiliating defeat.

Kubang Pasu has been Mahathir's stronghold in his over three decades political career.

Earlier, Mahathir appointed 12 new honorary members of the Kuala Lumpur Malay Chamber of Commerce, which includes his son Muhkriz, Transparency International-Malaysia president Ramon Navaratnam and local think-tank Asli chief executive officer Michael Yeoh.

Mahathir is a grand fellow of the chamber of commerce.

Watch 10-minute video of the press conference