Two leading political parties are expected to announce their presidential candidates in the second week of May, said highly-placed reliable sources.
Incumbent Ranil Wickremesinghe is to take his decision after considering the results of an opinion poll conducted islandwide by a leading international pollster.
At the same time, the Sri Lanka Podujana Peramuna will announce the candidate it supports.
The Samagi Jana Balawegaya, National People's Power and Mawbima Janata Party have already said their candidates would be Sajith Premadasa, Anura Kumara Dissanayake and Dilith Jayaweera respectively.