The DUP member who defeated former UUP leader David Trimble in the last Westminster election has voiced doubts about the decision to share power at Stormont with Sinn Féin.
David Simpson, along with his Upper Bann Assembly colleague Stephen Moutray, has said it was "premature" for his party to decide to share power with republicans on May 8th in the absence of any "credible testing period".
His comments follow the resignation of MEP Jim Allister from the party on Tuesday, 24 hours after the appearance of the Rev Ian Paisley and Sinn Féin president Gerry Adams holding their first meeting at Stormont.
The developments illustrate some of the tensions within the DUP since Monday and despite the apparent strong endorsement of the leadership position.
Lagan Valley MP Jeffrey Donaldson said he was surprised at the stance adopted by Mr Simpson and Mr Moutray since, he claimed, both had voted for the resolution at the DUP executive meeting last Saturday which set the party on course for powersharing with Sinn Féin.
The resolution, agreed after a 5½-hour meeting in Castlereagh on Saturday, was passed by 102 votes to 10. One of those voting against was South Down MLA Jim Wells. He admitted yesterday the days since Saturday's meeting "had cost him sleepless nights".
However, following soundings among his local party, he said he had decided to remain in the party and to voice his concerns from within the organisation.
Two DUP councillors in Dr Paisley's North Antrim constituency have already resigned while others have told The Irish Timesthey are unhappy with developments and will make statements on their future shortly.