Millions of Sri Lankans cast their votes on Saturday to select a new president who will face the task of cementing the South Asian country's fragile economic recovery following its worst financial crisis in decades.

More than 17 million of Sri Lanka's 22 million people are eligible to vote at the presidential election that has shaped up to be a close contest between incumbent President Ranil Wickremesinghe, main opposition leader Sajith Premadasa and left-leaning challenger Anura Kumara Dissanayake.

Voting begins at 7am local time and ends at 4pm, with counting scheduled to start shortly after.

"All arrangements are finalised to hold the election at over 13,000 polling stations countrywide and 250,000 public officials will be deployed to manage the election," said RML Rathnayake, head of Sri Lanka's election commission.

This is the first election since Sri Lanka's economy buckled in 2022 under a severe foreign exchange shortage leaving the Indian Ocean island nation unable to pay for imports of essentials including fuel, medicine and cooking gas.

Thousands of protesters marched in Colombo in 2022 and occupied the president's office and residence, forcing former President Gotabaya Rajapaksa to flee and later resign.

Buttressed by a US$2.9 billion bailout programme from the International Monetary Fund (IMF), Sri Lanka's economy has posted a tentative recovery but high cost of living remains a core issue for many voters.

Although inflation cooled to 0.5 percent last month and GDP is forecast to grow in 2024 for the first time in three years, millions still remain mired in poverty and debt, with many pinning hopes of a better future on their next leader.

Sri Lanka's ranked voting system allows voters to cast three preferential votes for their chosen candidates, with any candidate securing 50 percent of the votes or more declared winner.

If no candidate wins 50 percent in the first round there is a second round of counting between the two frontrunners, with the preferential votes of other candidates redistributed, an outcome analysts say is likely given the close nature of the election.

The Election Commission will formally announce the winner, probably on Sunday.

Whoever wins the election will have to ensure Sri Lanka sticks with the IMF programme till 2027 to get its economy on a stable growth path, reassure markets, attract investors and help a quarter of its 22 million population climb out of crisis-caused poverty. (Reuters)