Former Ulster Unionist MP Jeffrey Donaldson was expected today to confirm his defection to the Rev Ian Paisley’s Democratic Unionists.
The Lagan Valley MP was poised to announce his defection at a press conference in Belfast following his decision to stand down from David Trimble’s Ulster Unionists before Christmas.
Mr Donaldson is expected to be joined by two former colleagues in the Ulster Unionists’ Assembly team, Fermanagh South Tyrone MLA Arlene Foster and Lagan Valley MLA Norah Beare.
The trio quit last month after Ulster Unionists gave Mr Donaldson an ultimatum at a meeting of their 110 member executive to toe the party line or face disciplinary action.
Mr Donaldson and his supporters have fought a five-year battle with Mr Trimble’s wing of the party over their continued support for the Good Friday Agreement and their willingness to go into government with Sinn Féin.
The split between Mr Donaldson and Mr Trimble took a turn for the worse last summer when the Lagan Valley MP and two other Ulster Unionist MPs, the Reverend Martin Smyth and David Burnside, resigned the whip at Westminster.
A Belfast high court judge in July overturned a bid to suspend the MPs because the party hierarchy did not follow their rules properly.
A second bid to discipline Mr Donaldson, Mr Burnside and the Reverend Smyth was put on hold last September after David Trimble succeeded in persuading Ulster Unionist Council to call on the MPs to resume the whip.
Mr Trimble, however, suffered a blow in November’s Assembly Election when the rival hardline Democratic Unionists overtook his party to become the main voice in Unionists.
The DUP captured 30 seats but was today expected to extend that lead over the UUP by increasing its share of Stormont seats to 33.
The Ulster Unionists also fell behind the DUP in terms of the popular vote and finished behind Sinn Féin.
Announcing his decision to quit the UUP last month, Mr Donaldson claimed the party no longer held the values which he cherished.
He confirmed that he had been offered a place in the DUP’s negotiating team for the forthcoming review of the Good Friday Agreement.