KUALA LUMPUR • Former Malaysian prime minister Mahathir Mohamad is seeking to move a no-confidence motion in Parliament against his successor, Tan Sri Muhyiddin Yassin, when Parliament convenes on May 18.

The letter dated Monday sent by Tun Dr Mahathir to the Speaker of Parliament's Lower House, Tan Sri Mohamad Ariff Md Yusof, states his intention to table the motion as Mr Muhyiddin does not have the majority support of Members of Parliament to remain as Prime Minister.

The letter came to light a day after another sent by Sabah Chief Minister Shafie Apdal to Mr Ariff seeking a motion of confidence in Dr Mahathir went viral on social media on Wednesday.

But the motion by Datuk Seri Shafie, who is MP for Semporna in Sabah, was rejected by the Speaker as it was not in line with Article 43 of the federal Constitution, which relates to the authority of the king to appoint the prime minister.

"Therefore, I will not allow the motion to be brought to the sitting," Mr Ariff said in a letter responding to Mr Shafie's motion on Tuesday.

Mr Shafie confirmed earlier yesterday, after being pressed by reporters in Sabah, that he had sent the letter dated May 1 seeking the motion.

But the Parti Warisan Sabah president declined to elaborate on his reasons for seeking the special motion, saying that the matter would be deliberated at the appropriate time and place, The Star reported.

May 18 will be the first Parliament sitting in Malaysia since the so-called backdoor Perikatan Nasional (PN) government led by Mr Muhyiddin took over from the Pakatan Harapan alliance in March.

The latest moves by Dr Mahathir and Mr Shafie have reignited a political crisis in Malaysia that began on Feb 24, when Dr Mahathir resigned as prime minister, triggering a split in his Parti Pribumi Bersatu Malaysia party.

Members from Bersatu - including Mr Muhyiddin, and 11 lawmakers from Parti Keadilan Rakyat (PKR) - then left PH, prompting the collapse of the coalition government after it lost its parliamentary majority.

The breakaway group later joined forces with the Umno-led Barisan Nasional and Parti Islam SeMalaysia - parties that were not part of the PH pact that won the last general election in May 2018 - to form the PN alliance.

Despite PN taking power, PH has insisted that it, not Mr Muhyiddin or the PN, has the support of the majority of MPs.

Mr Shafie has remained friendly to the PH bloc and continues to support Dr Mahathir.

The one-day Parliament sitting on May 18 will be the first test of whether either side commands majority support of the 112 lawmakers necessary to govern the country.

Meanwhile, PKR president Anwar Ibrahim yesterday announced that the PH alliance has named him the opposition leader, The Star reported.

Datuk Seri Anwar made the announcement in a Facebook live video, saying the coalition has informed Parliament that he would be leading them.

"The decision has been made known to all opposition parties, including a faction from Parti Pribumi Bersatu Malaysia and Parti Warisan Sabah, that I have been named the leader of the opposition once again," he said.

Mr Anwar had held the position from June 26, 2013 to March 16, 2015 - during his time as MP for Permatang Pauh.

The current MP for Port Dickson replaces Umno's Datuk Seri Ismail Sabri Yaakob, who took on the role of opposition leader during the PH government.