With speculation rife that Umno deputy president Muhyiddin Yassin will be suspended from the party, secretary-general Tengku Adnan Tengku Mansor has chosen to remain mum.

"I don't know, I don't want to comment," he told Malaysiakini when contacted.

He, however, admitted there have been complaints brought against Muhyiddin over his attitude.

Asked if the party will follow up with action, he curtly replied: "No comment."

Muhyiddin was removed from the cabinet as deputy prime minister and education minister on July 28 for voicing out on the 1MDB affair and the prime minister's handling of it.

A source said it was almost confirmed that Muhyiddin's Umno membership would be suspended.

"The suspension is almost confirmed," he said.

Umno supreme council member Tajuddin Abdul Rahman, however, said he had heard nothing about any action to be taken against Muhyiddin.

"I don't know, I've heard nothing. When I say I heard nothing, I am not involved," he said.

He also revealed that none of the Umno supreme council members were talking about it.