KUALA LUMPUR, Sept 1 — Tun Dr Mahathir Mohamad by his own confession loves to work, but keeps his memory sharp and relaxes by reading — sometimes two books at one time.

In an interview published today, the 94-year-old prime minister reveals his habit of reading daily, and also his favourite writers: historical fiction writer Wilbur Smith and popular novelist Jeffrey Archer.

"I still read books. I read story books. I read something every day. Of course, I read my papers too,” he told Malaysia Airlines’ inflight magazine Going Places.

"When you read, the words that are there get recalled all the time and that’s how you remember. It’s like seeing somebody frequently and seeing that person once every three or four years.

"Sometimes, you cannot remember his name or recognise him,” he added, having also spoken of the need to use the brain actively like muscles in order to stay sharp.

In the same interview, Dr Mahathir shared his experiences of being pulled out from retirement in 2003 as the country’s prime minister of 22 years, when he was toying with the idea of writing books.

"When I retired in 2003, I thought I would never come back again. I wanted to rest, maybe write books. But one week after I stepped down, the new government reneged on what they promised to do. They had promised during our Cabinet meetings that they will continue with the railway project, the bridge to Singapore and other things.

"Because of this, many people were unhappy. So they came to see me. They said, please do something — those were their famous words. I asked them, what can I do? I’m not the prime minister anymore. But they insisted that I do something. I did try to contact the government to advise them, but to no effect,” he said.

Dr Mahathir said it was fortunate that he could still function and that he is trusted by the people to lead, noting that he was merely responding to the demands of his former critics who had called him a "dictator”, but wanted him to lead the Pakatan Harapan coalition.

Giving his nod of approval for the quality of "honesty”, Dr Mahathir said any movies made about him should be truthful, noting: "Tell the truth. Don’t embellish it or say, oh, he’s a great man. Tell the truth.”

In the same interview with Going Places, Dr Mahathir also shared other personal details, such as his grandchildren being his greatest treasure and his low use of his mobile phone.

"I don’t use my mobile phone very often. In fact, nobody knows my mobile number,” he said, adding that he himself does not know his mobile phone number.

As for the priciest item he had purchased for himself, Dr Mahathir said it was a "huge American car” under US automobile maker General Motors’ now-defunct Pontiac brand bought when he was practising medicine, noting: "In those days, it only cost RM12,000. It was a six-seater and the front seat was a bench that can seat three people.”

Dr Mahathir, who celebrated his 63rd wedding anniversary last month, said the tip to a lasting marriage was to "be tolerant” as a married couple are both "not perfect”.

"So both the wife and husband must tolerate the idiosyncrasies of one another. For example, I like to be on time. I always want to be punctual, but my wife is always late.

"At first, we quarrel, but after some time, I said she’s always going to be like that. So I have to put up with it, and she has to put up with me harassing her to "come, come, come, we’ve run out of time already,” he said.

His wife Tun Dr Siti Hasmah Mohd Ali had last year shared the secret to their long marriage, while Dr Mahathir himself has spoken of how he fell in love with her and of his preference for his wife to always be with him by his side.