UNP General Secretary Akila Viraj Kariyawasam is likely to resign from his post, party sources said.
Kariyawasam is set to resign from the post in order to allow both sides of the party to appoint a "mutually acceptable" General Secretary.
However, the Samagi Jana Balawegaya has confirmed to the Elections Commission that it will contest the upcoming Parliamentary election.
General Secretary of the party, Ranjith Madduma Bandara has written to the Elections Commission that the party will contest the Parliamentary election slated for April 25.
The Samagi Jana Balawegaya is led by Opposition Leader Sajith Premadasa.