Malaysian Prime Minister Mahathir Mohamad, at 94 the world's oldest leader, submitted his resignation to the king Monday after a bid by his allies to bring down the government and block the succession of leader-in-waiting Anwar Ibrahim
Beginning a working visit that is set to take Qatar-Malaysia ties to new heights, His Highness the Amir Sheikh Tamim bin Hamad al-Thani arrived in Kuala Lumpur on Wednesday evening.
The United Malays National Organisation (Umno) has governed the country for more than 60 years.
Sirul Azhar Umar was arrested and has been held in an Australian immigration detention centre since January 2015.
Najib Razak's coalition suffered a defeat at the May 9 poll, beaten by a reformist alliance led by Mahathir Mohamad, which broke their six-decade stranglehold on power.
Police arriving in a dozen vehicles converged on the home of corruption-tainted Najib Razak in Kuala Lumpur beginning late on Wednesday, drawing crowds of journalists and onlookers.
Malaysia's newly-elected Prime Minister Mahathir Mohamad said on Friday that the country's monarch has indicated he was willing to grant a full pardon to jailed politician Anwar Ibrahim immediately.
Najib Razak is under pressure to secure a strong mandate as he grapples with a multi-billion dollar scandal at a state fund and public anger over rising living costs.
Mahathir Mohamad, who ruled Malaysia for more than two decades and is now making another run at the top job aged 92, frequently traded barbs with Singapore's founding prime minister Lee Kuan Yew during his time in office.
Former Malaysian premier Mahathir Mohamad filed a suit against scandal-plagued Prime Minister Najib Razak, alleging corruption and abuse of power, his law firm said.