Sipitang MP Yamani Hafez Musa has not informed the Dewan Rakyat of his current party affiliation and is therefore still considered an independent MP.
In a statement today, de facto law minister Liew Vui Keong said this was confirmed by the Dewan Rakyat Speaker Mohamad Ariff Mohd Yusof.
Yamani was among a large group of Sabah politicians who defected from Umno last December.
By March, Bersatu had admitted most of them while Yamani's status was left hanging.
According to The Star, Yamani said he had submitted his application form to Bersatu earlier this year and he was not sure if he was admitted as a party member.
He said although party chairperson Dr Mahathir Mohamad had informally confirmed his membership, he was not sure if this had been made official.
Meanwhile, Sabah Bersatu chief Hajiji Mohd Noor said he believed that Yamani was indeed a member and has been proposed as the Sipitang Baru division's pro-tem deputy chief.
Yamani is the eldest son of Musa Aman, who was Sabah chief minister for 15 years until Sabah BN lost in the last general election. Musa is currently facing several corruption trials.
On Wednesday, the Federal Court threw out a petition to invalidate Yamani's victory during the last general election.
Should Yamani's Bersatu membership be confirmed, the government bench will have 140 MPs, just eight short of a two-thirds majority.