With each fresh attack, Najib Abdul Razak moves a step closer to the Umno guillotine, where many prominent heads have rolled.

Given the current situation, The Economist speculates that the blade may come down sooner than expected on the prime minister.

"Some had thought that his opponents in the party — now said to be rallying behind (deputy prime minister) Muhyiddin Yassin — would have to wait another year to gain enough support for a leadership challenge.

"But they may choose to move sooner than that," reports The Economist , citing the damning revelations swirling around Najib's brainchild 1Malaysia Development Bhd (1MDB).

The Economist also described Dr Mahathir Mohamad as a "meddling" former prime minister, who is "itching" for Najib to step down.

The magazine stated that while the opposition has smelled blood with regard to the 1MDB, Najib is more concerned about criticisms from within Umno.

"The fund has long attracted sniping from factions loyal to Mahathir," it added.

Borrowed time

On Wednesday, the Prime Minister’s Office (PMO) issued a statement saying the cabinet is confident 1MDB has committed no wrongdoings , while Najib requested the auditor-general to verify the firm’s accounts.

This, said The Economist , caused discontent to subside a little. However, it noted that Najib appeared to be on "borrowed time" ever since the 2013 general election.

Apart from 1MDB, the prime minister has also been under pressure after former police commando Sirul Azhar Umar threatened to reveal all on the murder of Altantuya Shaariibuu.

Though being cleared of any involvement in the case, the matter continues to haunt Najib.

Following this, the focus fell on his wealth when the PMO, in response to a report in the New York Times, attributed Najib's and his family’s lavish expenditure to inheritance.

Najib's four brothers then issued a statement expressing concern how this talk of wealth could soil the reputation of their late father.

They defended their father, second prime minister, Abdul Razak Hussein, as a frugal man.