The party confirmed that Donaldson has had his DUP membership suspended pending the outcome of criminal proceedings. 

He is scheduled to appear at the courthouse in the Northern Ireland border town of Newry on April 24, when more details of the charges against him are expected to be disclosed.

Donaldson, who has been MP for Lagan Valley southwest of Belfast since 1997, has spent recent months declining to confirm whether he would seek re-election as a member of parliament. Until now he had been widely tipped to gain a Conservative appointment to the House of Lords and hand the chance to retain his Commons seat to Little-Pengelly, who already was placed into his Northern Ireland Assembly seat.

The two other major unionist parties in Northern Ireland offered starkly different takes on the shock announcement.

Ulster Unionist Party leader Doug Beattie, who represents moderate pro-British opinion, said the circumstances of Donaldson’s arrest and charges “are of concern and in the public interest,” but “this is now a criminal investigation and it would not be proper to comment further.”

That didn’t stop the hard-line Traditional Unionist Voice leader Jim Allister, who has been leading an anti-Donaldson campaign in the hope of increasing splits within the DUP and forcing another U-turn away from power-sharing.