The UNP Working Committee meeting ended without a decision on Sunday night due to sharp differences of opinion over the party symbol.
The group supporting opposition Leader Sajith Premadasa disagreed with party leader Ranil Wickremesinghe's proposal to contest the election under the elephant symbol.
Premadasa was informed by the party leader that it was not possible to obtain other proposed symbols for the alliance due to legal impediments.
If the UNP-led alliance decides to contest under the elephant symbol, the nomination process will be handled by UNP General Secretary Akila Viraj Kariyawasam.
Premadasa is determined to launch the Samagi Jana Balawegaya this morning, with the participation of MPs and party leaders supporting him.