The Adamawa senators cited the leadership crisis in the PDP as the reason for their exit from the party.
The number of Peoples Democratic Party (PDP) senators dropped to 14 on Wednesday, following the defection of three PDP senators to the ruling All Progressives Congress (APC).
The senators are Aminu Abbas (Adamawa Central), Amos Yohana (Adamawa North), and Aliyu Bilbis (Adamawa South).
With their defection, the APC now has 84 senators.
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As of Tuesday, the PDP had 17 seats after the defection of Rivers West Senator, Ipalibo Banigo, who resigned her membership of the opposition party to join the APC.
Mrs Banigo, a former deputy governor of Rivers State, served from 2015 to 2023 under Nyesom Wike, the state's governor.
However, when the upper chamber reconvened for Wednesday's plenary, the three Adamawa senators also announced their exit from the PDP, the platform on which they were elected into the Senate.
They announced their defection to the ruling APC in separate letters read by the Senate President, Godswill Akpabio, during plenary.
Like other lawmakers who had previously left the party, the Adamawa senators explained in their letters that their decision was due to the PDP's lingering leadership crisis.
After reading the letters, Mr Akpabio welcomed the senators to the APC and directed that they be assigned new seats in the majority section of the chamber.
He also commended President Bola Tinubu for attracting opposition members to the ruling party, noting that such a development was rare in Nigeria's democratic history.
When the 10th assembly was inaugurated in June 2023, PDP had 59 senators.
With the development, the New Nigeria Peoples Party (NNPP), Nigeria Democratic Congress (NDC), and All Progressives Grand Alliance (APGA) have one seat each.
The Labour Party and the Social Democratic Party (SDP) currently have no representation in the Senate.
Adamawa, the home state of former Vice President Atiku Abubakar, had long been considered a stronghold of the PDP, until recently, when the governor, Ahmadu Fintiri, defected to the APC.
Mr Fintiri announced his decision in a statewide broadcast, stating that he took the step in the best interest of the development of Adamawa State. He added that members of his cabinet and other PDP officials in the state would join him in the ruling party.
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The governor had served as chairman of the party's national convention held on 15 and 16 November 2025, which produced Kabiru Turaki as national chairman.
Since the outcome of that convention, Mr Fintiri's body language suggested he was uncomfortable with decisions taken by the Turaki-led executive, particularly those directed at the faction of the party backed by the Minister of the Federal Capital Territory, Nyesom Wike.
Despite chairing the convention, he publicly opposed the expulsion of Mr Wike, former Ekiti State governor, Ayodele Fayose, former National Secretary, Samuel Anyanwu, and eight others during the party's national convention in Ibadan.
He instead called for dialogue to resolve the crisis among the party's warring leaders. However, the Turaki-led executive ignored his advice and issued expulsion letters to the affected members.
After the incident, Mr Fintiri distanced himself from PDP activities.
Earlier, the Speaker of the Adamawa State House of Assembly, Bathiya Wesley, alongside 15 PDP lawmakers, had defected to the APC, citing the party's lingering leadership crisis.
