UNP General Secretary Akila Viraj Kariyawasam said the UNP would make a final decision on the post on oppsoition leader on December 05.
Parliamentary group is expected to meet on Thursday to discuss the matter at length.
While a sizable group of parliamentarians support Sajith Premadasa for the opposition leader’s post, another group are exploring the possibility of proposing Speaker Karu Jayasuriya’s name to the post.
However, 57 MPs — the majority of UNP parliamentary group — have already pledged support to Premadasa.
The decision of the parliamentary group will be conveyed by the party General Secretary to the Speaker who will make the official announcement of the appointment.