Niue's former High Commissioner to New Zealand, O'Love Jaobsen, is expected to contest the premiership against caretaker leader Sir Toke Talagi.
Opposition members of the Assembly met yesterday to decide on their nominees for both premier and speaker.
The 20 seat legislature will sit today for the first time since last week's election, to vote for both roles.
The government caucus has already agreed to back Sir Toke for a fourth term as premier and re-nominate Togiavalu Pihigia as the speaker.
While the 5 opposition members have put forward Mrs Jacobsen as their nominee as premier, only four of them have agreed to back her.
Ms Jacobsen won the most votes for the common roll seats with Sir Toke finishing third.
Veteran opposition member Terry Coe got the second highest number of common roll votes but says he will not back Ms Jacobsen for premier.
The opposition has put forward Togia Sioneholo as their nominee as speaker.