Dr Mahathir Mohamad said PKR president Anwar Ibrahim did not support him despite the former premier arranging for his royal pardon and release from prison.
"He met a lot of people (to rally for support).
"He met rulers and foreigners instead of supporting me. He was critical of me," the nonagenarian told the Malaysia Gazette in an interview.
Mahathir and Anwar, who had been political nemeses for two decades, became allies in Pakatan Harapan to topple the Najib Abdul Razak-led Umno/BN coalition from power in the 2018 general election.
Following Harapan's victory in the polls, Mahathir kept his word and arranged for Anwar to be pardoned in relation to his sodomy conviction, which the latter has always maintained were based on fabricated charges.
Following this, Anwar returned to Parliament as the MP for Port Dickson and his relationship with Mahathir remained tense over the succession plan.
Eventually, Anwar agreed not to set a deadline for Mahathir to step down, but it was too late as the infamous Sheraton Move led to the Harapan administration's collapse in late February after 22 months in office.
Dr M - Anwar helped cronies amass wealth
In the Malaysia Gazette interview, Mahathir recalled how he admitted Anwar, a fierce Islamic activist in the 1970s, into Umno in 1982 despite resistance from other party members.
In Umno, Mahathir, whose first tenure as prime minister was from 1981 to 2003, said Anwar rose through the ranks and became his deputy in both the party and government in 1993.
"But when he became the deputy prime minister, he tried to topple me," he added.
Mahathir accused Anwar, whom he sacked as deputy premier in 1998, of using proxies and instigating protests to oust him.
He also accused Anwar of helping cronies amass enormous wealth and specifically mentioned current Umno president Ahmad Zahid Hamidi as one of them.
"That is Anwar's method," he added.
On Anwar's latest claim of having the majority to form a new government, Mahathir said he heard a similar claim in the past and is unsure if the former would succeed this time.
However, he is sure that Prime Minister Muhyiddin Yassin is in a precarious position.
"Muhyiddin being toppled is one thing, the question of whether Anwar has the support (of the MPs) is another," he added.
On Sept 23, Anwar, for the third time in his political career, claimed that he had the numbers to form the government but there have been no updates since.
Muhyiddin still chaired the cabinet meeting yesterday.