The Ulster Unionist leader, Mr David Trimble, is reportedly facing a fresh party rebellion over suggestions for a formal merger between the Ulster Unionists and the British Conservative Party.
At the same time, anti-agreement dissidents are expected to await the outcome of Saturday's UUP Executive before deciding whether to convene yet another meeting of the Ulster Unionist Council in a renewed attempt to have Sinn Féin removed from ministerial office or to force the UUP leadership to quit the power-sharing Executive.
The UUC president, the Rev Martin Smyth MP, renewed calls for "sanctions" against Sinn Féin during Northern Ireland Questions in the Commons yesterday, amid indications that a meeting could be called for the beginning of July.
Meanwhile, Sinn Féin's increasingly successful 32-county operation and expectations the SDLP might follow suit in a realignment with Fianna Fáil are cited as the stimulus for the latest phase of Belfast-London talks designed to place Ulster Unionist interests in a UK-wide context and to maximise the party's influence at the heart of British politics.
However, Mr Trimble apparently surprised his party officers at their meeting in Belfast last Friday with his enthusiasm for a renewed Conservative and Unionist pact, which insiders say could see him or his nominees eventually join Mr Iain Duncan Smith's shadow cabinet in London.
It is understood that opposition to the proposed restoration of the Tory-Unionist link - first reported in The Irish Times last summer - was led by Sir Reg Empey, the Enterprise, Trade and Investment Minister at Stormont, previously thought a key ally of Mr Trimble.
Ulster Unionist MPs at Westminster took the Conservative Party whip before the suspension of the Stormont parliament by the Heath government in 1972.
The party's formal affiliation to the Conservative National Union was severed in the angry aftermath of the Anglo-Irish Agreement in 1985.
Even some "in principle" supporters of renewed ties with the Conservatives are understood to question the wisdom of such a development as the UUP prepares for what could be a decisive battle with the Democratic Unionists in next year's Assembly elections.
Some well-informed sources suggest the development would only be of mutual benefit following UUP success in next year's election and the orderly transfer of Mr Trimble's leadership of the devolved administration.
In such circumstances there is no doubt some Conservatives believe Mr Trimble would be a formidable addition to Mr Duncan Smith's front-bench team.
Mr Trimble held exploratory discussions on this issue last summer with the then Conservative chairman, Mr Michael Ancram. Following that, UUP MPs Mr Roy Beggs and Mr Jeffrey Donaldson are believed to have held inconclusive talks with Tory MP Mr Dominic Grieve and Mr John Taylor of the Conservative Convention.
The speculation at Westminster last night was that resumed discussion of the issue would seem to follow recent London talks between Mr Trimble and Mr Duncan Smith.
In the Commons yesterday, Mr Trimble told Dr John Reid, the Northern Ireland Secretary, that belief in the devolved institutions would only be sustained by popular confidence which was "at a low ebb" because of "the popular belief . . . that no matter how badly republicans behave, this government will do nothing to constrain them and that it has, literally, allowed them to get away with murder".