It is now official. Nigeria’s Senate president said on Tuesday he was leaving the country’s ruling party, a further blow to President Muhammadu Buhari months ahead of an election he plans to contest and just a week after a raft of defections. He will return to his former party, the PDP, he announced on his twitter handle.

However, Saraki may not leave alone. Insiders suggest that a few more senators would join him which would further swell the ranks of the PDP in the Senate.

Saraki is the most high-profile figure to leave the All Progressives Congress (APC). Last week, 16 lawmakers in the upper house of parliament left the APC, as did 32 others in the lower house.

The loss of influential figures and divisions in the party threatens to split support for Buhari within powerful patronage networks and among voters ahead of the presidential election scheduled for February 2019.

“I wish to inform Nigerians that, after extensive consultations, I have decided to take my leave of the All Progressives Congress (APC),” Saraki said on his Twitter feed.

A spokesman for Buhari said the APC would comment later.

All but two of the 16 senators who left the APC last week joined the opposition People’s Democratic Party which meant the ruling party lost its majority in the upper house, which is likely to make it harder for Buhari to pass legislation.