Former Malaysian premier Mahathir Mohamad said he is not going after the country’s top job, and will instead focus on defeating Prime Minister Najib Razak in the coming elections.

The 92-year-old Mahathir, who held the top job from 1981 to 2003, had previously said he was willing to temporarily stand in as prime minister if the opposition won the next election. But he told CNBC on Friday that the opposition has a number of candidates capable of leading the Southeast Asian country.

“I’m not thinking about ruling; I’m thinking about defeating Datuk Seri Najib in the next elections and it would seem that lots of people are responding to what I’m doing,” Mahathir said. “We are confident we will win, but of course we have to deal with a man who’s going to stop at nothing in order to stay in power.”

Najib’s office didn’t immediately return CNBC’s emailed request from comment.

Mahathir refused to reveal the names of the other potential candidates for prime minister, however, saying that doing so would detract the opposition from its political fight.

“(Naming them) will cause a lot of people to go into debate and bring up all kinds of false accusations against them, and we will be preoccupied trying to defend a candidate who may never become the prime minister,” he said on CNBC’s “Street Signs.”

Mahathir, Malaysia’s longest-serving prime minister, launched the Malaysian United Indigenous Party (PPBM) earlier this year in the aim of overthrowing Najib, whose domestic and international standing has been hit amid his alleged role in a multi-billion dollar corruption scandal. Najib has denied the accusations.

The scandal, involving funds from state investment firm 1MDB, has been investigated in at least six jurisdictions, including the United States, Switzerland and Singapore.

Mahathir, often honing in on the 1MDB issue in his political campaigns, has unsuccessfully tried other means to topple Najib, including a vote of no-confidence and reporting the prime minister’s misdeeds to the police. Now, he is leading the opposition coalition, called Pakatan Harapan, to achieve his goal.

Pakatan Harapan consists of two other political parties besides Mahathir’s PPBM: the Democratic Action Party and People’s Justice Party, which collectively hold 71 out of 222 seats in Malaysia’s parliament.

He predicts general elections will be called either at the end of this year or early next year.

— CNBC’s Nyshka Chandran contributed to this report.