Malaysian Prime Minister Mahathir Mohamad, at 94 the world’s oldest leader, submitted his resignation to the king Monday after a bid by his allies to bring down the government and block the succession of leader-in-waiting Anwar Ibrahim.

The shock move followed 24 hours of political drama which saw an attempt by Anwar’s rivals within his own “Pact of Hope” coalition, which stormed to a historic election victory in 2018, and opposition politicians to form a new government.

The coalition would reportedly have excluded Anwar, Mahathir’s presumptive successor, and most of the lawmakers from his party, which would have stopped him becoming premier any time soon.

Anwar and Mahathir have a notoriously stormy relationship but they reconciled ahead of the 2018 polls, and Mahathir has repeatedly promised to hand over power to his former foe.

The bid appeared to have fizzled out by early Monday, however — before Mahathir’s office announced he had “sent a resignation letter as prime minister of Malaysia” to the king at 1:00 pm.

What would happen next was far from clear, however.

Anwar was due to meet the king Monday afternoon. While the monarch’s role is largely ceremonial, he confirms the appointment of the country’s prime minister and Anwar could be hoping to persuade him that he has enough support from MPs to form a government, observers said.

However, Mahathir’s party Bersatu also announced it was leaving the “Pact of Hope” coalition — suggesting they could be making their own attempt to form a government.

Earlier, two of Anwar’s rivals from his People’s Justice Party, Mohamed Azmin Ali and Zuraida Kamaruddin — seen as key figures in leading the bid to form a new government and block his ascent — were sacked, the party announced.