Dr Mahathir Mohamad, who is adamant on seeing Prime Minister Najib Abdul Razak’s head roll, will attend the Umno annual general assembly next week.

According to Umno secretary-general Tengku Adnan Tengku Mansor, the former party president of 22 years and his wife Dr Siti Hasmah Ali have confirmed their attendance.

“Tun Mahathir has given an answer that he and Tun Dr Siti Hasmah will come,” he was quoted as saying by Bernama today.

Mahathir had previously claimed that Umno is now “Najib’s party”, because those who criticise him are silenced or gagged.

He was responding to the decision to prevent deputy president Muhyiddin Yassin from addressing the delegates.

Mahathir had also complained of how he is being allegedly prevented from meeting Umno members.

Last week, the former premier penned an open letter to Umno members, warning them about the possibility of defeat in the next general election if Najib remained at the helm.

"Reject his leadership before GE14 so that Umno would be safe and be able to win the election to remain as a fair government to all," he added in the letter posted on his blog

Meanwhile, Najib has dismissed the allegations against him and accused Mahathir of being part of a conspiracy to topple him.