Former Prime Minister Tun Dr Mahathir Mohamad has denied that he is prone to breaking his promises as what some parties claim.

Dr Mahathir said he would fulfil his promises as he had done before.

"If I make a promise, I will keep my promise.

"Can check how I have behaved since I became prime minister. Even before that, I have never broken my promise," he said in an interview with the Malaysiakini portal.

Dr Mahathir gave an example of how he kept his promise to step down in 2002, allowing for a smooth transition of power after 22 years of his leadership.

"At that time, (Lim) Kit Siang said I would never resign. This was all a joke. But as we all know, until the time came, I resigned. I never broke my promise. Show me where did I break my promise?" he said.

During the interview, Dr Mahathir also disclosed the talks on Pakatan Harapan (PH) Plus’ prime ministerial candidate.

He said the Warisan party was of the opinion that he should be appointed as prime minister once again to prove "the Malay party" was part of the coalition.

"If the PH seems as if the coalition is a mixture of races, I fear that the Malay members of the Dewan Rakyat will not support. And if there's no support, never mind.

"Whether to be the prime minister, or to be anything, but without the support we cannot become the government.

"Even the election of a candidate as prime minister is meaningless. It is not the candidate that is important, but the victory by getting a majority that is important.

"I cannot guarantee but that was our experience, if there is no Malay party support, the opposition never wins," he said.

Dr Mahathir explained that when PH formed the government, the practice of putting politicians in charge of government-related entities had been replaced by professionals who fit the role.

"(Now) it's not just Najib's (Razak's) past mistakes that need to be corrected, but Muhyiddin's mistake is much bigger.

"We have changed from politicians to (professionals) (in leading the GLC), people who are proficient in business and so on.

"Now he (Muhyiddin) is turning back to the politicians. Again, there would be misappropriation, theft of money and so on," he said.

The Langkawi MP also said that if the PH Plus’ plan succeeded in taking over the government, the coalition should also look at political interventions in the administration and the judicial system.

Should PH Plus fail to take over the government, Dr Mahathir said he would have no choice as he was not prepared to work with Muhyiddin.

"If we can't win, what to do? Wait for the election. In the election, the people will decide even though the people will be bribed as before.

"Because cash is king (money is everything). The slogan is back, supported by those who (formerly) opposed it.

"(But) I'm sure the public generally does not like the practice of cash is king. As in the 14th general election, they rejected cash is king, I believe in the 15th general election (people will again reject).

"Although a lot of money will be given to the people to support Muhyiddin’s party, Umno and PAS, I am confident the people will not vote for them," he said.