Opposition leader Anwar Ibrahim’s reformist, multi-ethnic Pakatan Harapan coalition along with the pro-Malay Islamist coalition of Muhyiddin Yassin failed to gain a majority on Saturday.
The political uncertainty raises concerns over Malaysia’s slowing economic growth and rising inflation. No prime minister has remained in power for more than 22 months since the previous election in 2018.
The National Front, led by the United Malays National Organisation (UMNO), which has ruled the country for most of its independent years suffered its worst electoral defeat by winning just 30 seats in the federal parliament.
Mr Ibrahim's reformist bloc secured 82 seats, far short of the 112 needed for a simple majority, whereas the Malay nationalist alliance led by former prime minister Muhyiddin Yassin trailed with 73 seats.
Mr Yassin's coalition managed to secure the support of blocs in two states on Borneo island that jointly have 28 seats.
Former Malaysian prime minister Mahathir Mohamad, 97, lost his seat for the first time in 53 years.
King Sultan Abdullah Sultan Ahmad Shah, who initially set a 2pm Monday deadline for political leaders to submit their choice for prime minister and an alliance, extended the time by another 24 hours after parties failed to meet consensus.
UMNO president Ahmad Zahid Hamidi, who has emerged as a kingmaker, said his alliance formed a negotiation committee to hold talks with both blocs.
Mr Anwar on Monday said he met with some leaders of the incumbent National Front to discuss a potential alliance and was "very pleased" with the talks.
"I am satisfied as this negotiation was on the need to form a stable government that's inclusive. I am still very optimistic that we will be able to form a government," he told reporters.
His coalition later issued a statement saying it has entered into a "serious negotiations phase" with the National Front.
In a turn of events, Hishammuddin Hussein, a UMNO vice president, issued a statement on Facebook to reiterate his refusal to support Anwar’s bloc. “I am willing to be fired by the party but will never change this firm stance,” he said.
Mr Muhyiddin's Perikatan Nasional alliance, which includes the PAS Islamist party that secured the largest number of parliamentary seats of any single party and called for the imposition of sharia law, claimed that it had majority support to form the government.
He, however, did not disclose where the support came from.
"I am confident I will obtain enough support from lawmakers that will enable me to be appointed by the king as prime minister," Mr Muhyiddin said.