Conservative Party leader David Cameron with Ulster Unionist leader Sir Reg Empey at a conference last December
The Ulster Unionist party's ruling executive is due to meet to give its verdict on proposals for a partnership with the Conservative Party.
The most difficult issue has been which name the new grouping will take, as most assembly members opposed Tory plans to drop the word "Ulster".
It is understood the new name will be the Ulster Conservatives and Unionists but the word "party" will not appear.
A joint committee from the two parties has finalised the proposals.
The Tory-Ulster Unionist partnership has been under discussion since last July.
The two parties have agreed to select joint candidates in future European and Westminster elections.
Conservative leader David Cameron told the Ulster Unionist conference last December that the new pact would give voters in Northern Ireland a "greater say in national and international politics".
The proposals will be put before the Ulster Unionist Executive and the area council of the Northern Ireland Conservatives on Thursday evening.
BBC Northern Ireland political correspondent Gareth Gordon said: "It's still unclear what view the sole Ulster Unionist MP, Lady Sylvia Hermon, who's known to be unhappy, will take. She's entitled to attend this evening's meeting."