India has begun evacuating thousands of villagers and halted port operations ahead of a cyclone expected to hit its east coast this week, officials said, piling pressure on emergency services already grappling with the coronavirus pandemic.

"We have to evacuate people from low-lying areas, and protect them from the coronavirus too," said a senior official of India's home ministry who spoke on condition of anonymity. "It's not an easy task."

The cyclone, expected to make landfall on Wednesday, comes as India eases the world's longest lockdown, imposed in April against the coronavirus which has infected more than 96 169 people and killed 3 029 in India.

The states of Odisha and West Bengal sent disaster management teams to move families from homes of mud and thatch to places of shelter from the severe cyclonic storm, Amphan, which is expected to gain strength over the next 12 hours.

Authorities at the port of Paradip in Odisha ordered ships to move out to sea to avoid damage as the cyclone formed over the Bay of Bengal was likely to intensify into a super cyclonic storm.

Cyclone season

"Operations have been wound down," said Rinkesh Roy, chair of the Paradip Port Trust. "We are clearing the port."

"The extremely severe cyclonic storm 'Amphan' ... is likely to gain more strength and intensify further into a super cyclonic storm in the next 12 hours," weather officials said in a statement forecasting heavy rain in eastern and southern areas.

The cyclone season usually runs from April to December, with severe storms forcing the evacuations of tens of thousands, causing widespread death and damage to crops and property both in India and neighbouring Bangladesh.

India, with a coastline of 7 516km, gets hit by more than a tenth of the world's tropical cyclones, the bulk of them hitting its eastern coast around the Bay of Bengal.