Mukhriz Mahathir has been ousted as chief minister of the northern Malaysian state of Kedah, ending a long-drawn power struggle in the ruling party and signalling a stronger hand for embattled Prime Minister Najib Razak.

The exit of Mukhriz, the son of strongman Mahathir, comes after the father-son duo's sustained criticism of Najib over the 1MDB scandal and the $681 million the prime minister received in his personal account. Mukhriz resigned after the Kedah Regency Council informed him that he had lost the support of the majority of lawmakers in the state assembly.

Mukhriz Mahathir resigns as Kedah chief minister
Mukhriz Mahathir (right) in a file photo. Reuters

"The actual reason for removing me is because of my criticisms against the prime minister, which he himself has admitted," Mukhriz said in a statement after announcing his resignation. "The criticism is about the 1MDB scandals and the 2.6 billion ringgit donations and the impact of cost of living on people arising from GST," he said.

Mukhriz said being no longer the "mentri besar" in Kedah means it is easier for him to criticise the prime minister.

Mahathir Mohamed, the country's longest serving prime minister, has repeatedly said Najib should resign. He says the United Malays National Organisation (UNMO), which has been in power since 1957, will lose the next election if it faces people under Najib's leadership. Mukhriz and his father have been in the frontline of political attack of Najib, whose reign is tainted with allegations of corruption and the poor state of economy.

Removing detractors

However, Mukhriz's ouster strengthens Najib, who has had detractors removed from positions of influence of late. His deputy, Muhyiddin Yassin, was removed in July after he demanded clarity in the 1MDB scandal.

Malaysia's attorney general absolved Najib of any financial misconduct but the opposition points out that other countries like Switzerland, Singapore and France are investigating the 1MDB transactions. Mukhriz said the UNMO is at its weakest point, with scandals after scandals affecting the reputation of the federal government.

"We can't take it anymore, we can't even hold our heads up overseas," he said.