COLOMBO: Sri Lanka's fuel stocks will last for about five more days, its power and energy minister said on Thursday, as the island nation awaits official confirmation from the Indian government for a new $500 million credit line for fuel.

The country of 22 million people is caught in its worst financial crisis in seven decades after its foreign exchange reserves dwindled to record lows, with dollars running out to pay for essential imports including food, medicine and fuel.

Chronic fuel shortages have worsened this week with kilometres-long lines at some gas stations countrywide, leading to sporadic protests as vehicle owners wait, sometimes overnight, for petrol and diesel.

The stocks cover fuel for vehicles, some industries and essential services. A month ago, the prime minister said there was only enough petrol for one day.

Sri Lanka is unable to make $725 million in overdue payments to suppliers and also struggling to open letters of credit for future shipments, Power and Energy Minister Kanchana Wijesekera said.

"We are struggling to get fuel supplies due to our forex issues and the government is working to manage existing stocks of diesel and petrol until 21 June," he told reporters. "We are finding it very difficult to meet demand and stocks could run out faster if we do not cut back on non-essential travel and stop hoarding fuel."

"We are expecting a petrol shipment within the next three days and another two shipments in the next eight days," he added.

Sri Lanka is waiting for official confirmation on a $500 million credit line from the India government's Exim Bank, which Wijesekera said would be used to fund fuel shipments for the next few weeks.

India has been a key supporter during the financial crisis, having poured in about $3 billion in assistance, including a $1 billion credit line for essential imports and a $400 million swap.

Sri Lanka has reached out to multiple countries, including Russia, to discuss fuel import options that would provide supplies worth several months, Wijesekera said.

The country is also in talks with the International Monetary Fund for a bailout package and a delegation from the lender is expected to arrive in Sri Lanka on 20 June