President Anura Kumara Dissanayake had said last week that the island nation would need at least $1.66 billion in 2026 -- in addition to the $166 million he said the government would spend this year -- to rebuild and recover from what he described as the "most challenging natural disaster" to hit the country.

Parliament Speaker Jagath Wickramaratne on Sunday issued a notice for an urgent meeting of the legislature, which had gone into recess after approving the 2026 budget earlier this month and was not scheduled to meet again until January 6.

"I have summoned the parliament to meet on Thursday (18th)... having been requested so to do by the Hon. Prime Minister (Harini Amarasuriya)," the Speaker said in a gazette notification.

Officials at the country's finance ministry told AFP that the meeting was being held to approve next year's expenditure for cyclone recovery.

Official figures show that 643 people were killed, with another 184 still missing, following landslides and floods triggered by the cyclone.

At least 2.3 million people -- just over 10 percent of the country's population -- were affected by the devastating calamity. Nearly 75,000 people remain housed in state-run camps.

An official leading the recovery effort has estimated that overall damage could cost up to $7 billion.

The United Nations last week set up a $35.3 million fund to provide food and temporary shelter to 658,000 of the worst-affected people.

The fund excludes reconstruction of damaged infrastructure or private property and focuses solely on immediate basic needs.

The United Nations' top envoy to the country, Marc-Andre Franche, said last week $9.5 million had already been secured, with the European Union, Switzerland, Britain and the United States among donors pledging funds.

The United Nations urged member states and other donors to help raise the remaining $25.8 million.

A quarter of Sri Lanka's population was living in poverty when the cyclone struck, Franche said, urging the international community to assist the devastated nation.

Sri Lanka is also recovering from its worst-ever financial crisis.

It defaulted on $46 billion of external debt in April 2022 and secured a $2.9 billion bailout from the International Monetary Fund in early 2023.