The 225-seat parliament will vote to choose new leader, who will have to address country's economic and political collapse amid protests, with Ranil Wickremesinghe seen as frontrunner.
Gotabaya Rajapaksa, 73, fled Sri Lanka after protesters demonstrating against the country's worst-ever economic crisis overran his palace on the weekend.
Regular citizens, exasperated by months of crippling economic crisis, occupied government residences after three months of protests.
Sri Lankan protesters, who are occupying President Gotabaya Rajapaksa's residence in the capital Colombo, say they will won't leave the premises until Rajapaksa actually leaves the office.
Cash-strapped Sri Lanka sharply hiked fuel prices to a record high, causing further pain to the country's 22 million people in its worst crisis since independence.
Police meanwhile have arrested two lawmakers from the Rajapaksas' Sri Lanka Podujana Peramuna in connection with last week's violence when anti-government protests turned deadly.
President Gotabaya Rajapaksa promises to appoint new premier, empower parliament and abolish the all-powerful executive presidential system amid political crisis and violence triggered by worst economic crisis in memory.
There have been flare-ups of violence around the country despite stringent security measures, as protesters continue shouting slogans against the government while defying a curfew.
Five people were killed and nearly 200 wounded as prime minister Mahinda Rajapaksa resignation which did little to calm public anger.
Violence erupts among protesters and trade unions call for protests throughout this week over the worst economic crisis in the country's history.
A majority vote in the 225-member Parliament would be needed to remove Mahinda Rajapaksa and the Cabinet from power in the South Asian island country.
Also, the Sri Lankan government will sell long-term visas to attract foreign currency after the island nation ran out of dollars to pay even for food and fuel in the wake of a crippling economic crisis.
Subscribe to our Youtube channel for all latest in-depth, on the ground reporting from around the world.
Copyright © 2022 TRT World.