Umno supreme council member Abdul Rahman Dahlan said deputy president Muhyiddin Yassin will be brought before the party's disciplinary board to face possible suspension, for continuing to defy party orders to cease criticising the leadership.

"When a decision has been made by the supreme council, it binds the president, his deputy, and all Umno members, in the context of that decision.

"So if the deputy president disobeys the unanimous decision of the supreme council, like any member who ignores the order, he faces the risk of disciplinary action," he said.

Rahman said this after launching a solid waste management public roundtable in Kuala Lumpur today.

Yesterday, fellow supreme council member Nazri Abdul Aziz said he would propose that the disciplinary board suspend Muhyiddin as deputy president at the next meeting of the council.

This was because the former deputy prime minister's incessant attacks against party president Najib Abdul Razak were debilitating to the party, Nazri said.

Asked if the council has the power to expel Muhyiddin, Rahman said that it was normal procedure, but such a move would have to be first referred to the disciplinary board, which would investigate and come up with recommendations for further action.

When asked if Muhyiddin's fate will be decided in the council's meeting tomorrow, Rahman said that the Pagoh Umno chief is the management committee's chair and could not be expelled without cause.

"Oh no... we will properly go through the process... what I mean is... that we cannot simply decide tomorrow, not just like that."

"Even if there is a proposal to take action, it must go through the investigation stage and other processes via the Umno disciplinary board. I do hope that the board will be fair in this matter," he said.

Rahman's sentiment was matched by another supreme council member Reezal Merican Naina Merican who said in a statement that stern action must be taken to stop the attacks against Najib which may drag the party into an untenable and uncomfortable political position.

Reezal added that his calling for action against Muhyiddin does not mean that he is disrespecting the deputy president but that he values the harmony of the party and its constitution more.