Former deputy premier Muhyiddin Yassin has urged his ex-boss, Prime Minister Najib Abdul Razak, to heed the call by the Conference of Rulers for the government to resolve the 1MDB imbroglio.

Muhyiddin said the Malay rulers would not have made a statement on 1MDB if it was not an issue of national importance.

"When the sultans commented on 1MDB it shows that their majesties believe it to be a huge issue, and shows their concern about the negative impact of the 1MDB issue on the people and country.

"The person who should uphold the sultan's decree is the prime minister as the head of government. The responsibility to solve this issue ultimately rests on his shoulders," he added in a statement today.

The Conference of Rulers yesterday decreed that the probe into 1MDB be completed as soon as possible and the wrongdoers, if any, be punished.

They said if the 1MDB issue is not dealt with intelligently, and continues to drag on, it will damage the economy and the people's welfare.

In line with this decree, Muhyiddin said Najib must ensure the agencies investigating 1MDB conduct their work transparently without interference or meddling by any party.

If any guilty parties are identified, Muhyiddin said, action must be taken immediately without fear or favour.

Muhyiddin has been a staunch critic of 1MDB, a stand that resulted in him being axed from the cabinet in late July.

US financial daily The Wall Street Journal had reported that 1MDB funds had made their way into Prime Minister Najib Abdul Razak's personal bank accounts.

Najib, however, has denied any wrongdoing or that he had used 1MDB funds for personal gain.

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