Umno is monitoring seven leaders for possible disciplinary infractions, according to secretary-general Tengku Adnan Tengku Mansor.

He said this when quizzed on possible action being taken against Dr Mahathir Mohamad who has openly urged that Prime Minister Najib Abdul Razak's be ousted.

"There are seven leaders who we are monitoring.

“If we see the need to take action, we will send investigation papers to the disciplinary board," he told a press conference in Kuala Lumpur today.

However, he did not specify who the seven were, or why they were being monitored.

When pressed further on why Mahathir was not being disciplined, Tengku Adnan said his urging that Najib quit office was just a personal opinion.

Meanwhile on a related matter, the Umno secretary-general said the Pusat Bandar Taman Chempaka Umno branch would be asked to explain itself for holding a talk featuring Mahathir on Saturday.

He then swiftly changed topic and urged outsiders like former MCA president Ling Liong Sik to stay out of Umno matters.

“We know how to solve our own problems,” he said.

Liong had recently made headlines by joining the chorus of those who want Najib to step down.

Tengku Adnan then told the media not to muddy the waters and pit former leaders against current leaders.

“Enough is enough,” he said.