KUALA LUMPUR - Former Malaysian prime minister and now opposition leader Mahathir Mohamad says he will be prime minister for two years should Pakatan Harapan (PH) win the 14th general election.

"I can't stay for very long. At the most, I can last for two years," said Dr Mahathir.

At 92, he will become the world's oldest person to be voted prime minister if he wins the upcoming polls.

He told Japanese newspaper Mainichi Shimbun in an interview conducted last month he was still up for the fight against the ruling coalition Barisan Nasional (BN), even though he acknowledged it would be an uphill battle.

The BN is considered to have the upper hand in the upcoming polls, which must be held by August.

"I decided to eventually form a party and this party needs to work with other opposition parties if it is going to contest against BN and all the opposition parties felt that I should take the lead," he told Mainichi.

Dr Mahathir has said he is likely to stand in the Langkawi or Kubang Pasu parliamentary ward, both in Kedah state, or in the Putrajaya seat.

Prime Minister Najib Razak's BN holds a comfortable majority in Parliament but lost the popular vote for the first time at the last polls.

However, the opposition has since fractured with Parti Islam SeMalaysia (PAS) going its own way and even cooperating with the ruling party Umno on Islamic issues.

Pakatan Harapan, an alliance of Parti Keadilan Rakyat (PKR), Dr Mahathir's pro-Malay Parti Pribumi Bersatu Malaysia (PPBM), the Chinese-centric Democratic Action Party and moderate Islamic party Parti Amanah Negara, announced earlier this month that Tun Mahathir is the opposition's candidate for prime minister if it wins federal power.

Dr Mahathir's candidacy drew protests from certain quarters, who hold him responsible for decisions during his 22-year-tenure which eroded the independence of national institutions and curbed civil liberties, reported The Malaysian Insight.

He told Mainichi that if he becomes prime minister, he intends to eventually hand over the role of prime minister to jailed opposition leader Anwar Ibrahim when the latter is released from prison.

Anwar is set to be released in June, but he cannot run for political office for five years after his release, unless he is pardoned by the King.

Dr Mahathir said in the interview that the opposition coalition will do its best to obtain a royal pardon.

"We will try. We will do our best to get a royal pardon," Dr Mahathir told Mainichi.

Dr Mahathir also touched on the Najib administration's alleged growing relationship with China, saying that Malaysia is no longer globally neutral.

He accused the current Malaysian leader of being "too close to China".

"We are no longer neutral," he said in the interview which was published on Feb 3.

Reflecting on his previous time in power, Dr Mahathir said: "Malaysia's policy was neutral. We were friendly with every country. Whether China or Japan or Korea or America. We were friendly. If they do something wrong, we feel we have the right to criticise them.

"We don't want to be aligned to anybody."

Dr Mahathir has blogged several times and spoken to the media about his concern that Mr Najib is allowing mainland Chinese companies to buy vast swathes of land, particularly in southern Johor.

His rhetoric on Chinese projects in Malaysia is seen as part of a campaign to unseat Mr Najib.

Mr Najib has slammed the opposition's criticism of the government's good ties with China as being extremely myopic.

In a recent speech to business leaders and entrepreneurs, he dismissed claims by critics that his government has compromised on sovereignty by allowing huge investments by China's state-owned firms into key infrastructure projects.

"We received RM63 billion from China and Hong Kong but Japan's RM70 billion investments doesn't 't seem to trigger anyone warning we are selling our country to the Japanese," he told Invest Malaysia 2018 event on Jan 23, an obvious dig at Dr Mahathir's own "Look East" policy in the 1980s.

Mr Najib cautioned there was a concentrated campaign to sabotage Malaysia's economy for political gain.

"Challenges at 1MDB, were amplified and used as a tool to suggest that our economy was collapsing. .

Johor Sultan Ibrahim Sultan Iskandar has also responded to Dr Mahathir, saying he was "deeply offended and hurt" by the attacks against mainland Chinese investments in the southern state.

"During his tenure as prime minister, he was asking Malaysians to 'Look East', but now he is criticising when Chinese investors come here to invest," said the Sultan in an interview with The Star last year.

He added that Dr Mahathir was "playing the politics of fear and race which has no place in Johor as I do not believe in racial politics".