The DUP leader Jeffrey Donaldson is expected to be approved as one of his party's election candidates in Lagan Valley at selection convention on Thursday.
It is understood the DUP plans to run two candidates in the constituency in the forthcoming Assembly election in May, and Mr Donaldson and the former First Minister Paul Givan - a current MLA for Lagan Valley - will be the only two names put forward.
It had been unclear whether the DUP would run two or three candidates in the constituency. Last week Mr Donaldson said the party was reviewing whether to run three candidates, as had previously been indicated, in order to maximise unionist representation.
If elected Mr Donaldson - who is currently the MP for Lagan Valley - must resign his seat at Westminster in order to take his place in the Assembly.
Mr Donaldson rejected suggestions earlier this week that had chosen not to take up a vacant Lagan Valley seat so that he could remain as an MP and avoid triggering a by-election until after the Assembly election on May 5th.
The position became vacant after the Lagan Valley MLA Edwin Poots transferred to South Belfast to replace Christopher Stalford, who died last month.
DUP councillor Paul Rankin was co-opted to replace Mr Poots. He will serve only two weeks as an MLA as the Assembly must be dissolved at the end of the month to allow the election to take place.
Mr Donaldson said he intended to “lead from the front” in the election.