Heavy rains and winds lashed two eastern Indian states and parts of Bangladesh hours before a powerful cyclone made landfall on Wednesday, with rescue teams evacuating millions of villagers to higher ground in an operation complicated by the coronavirus pandemic.

Bangladesh's disaster management officials said they were working on a war footing to evacuate about two million people from coastal areas as Cyclone Amphan approached from the Bay of Bengal.

The weather department in India said Amphan was likely to weaken into an extreme severe cyclonic storm and cross the coast near West Bengal state or Bangladesh by noon local time (0630 GMT).

An Indian federal home ministry official said West Bengal and neighbouring Odisha state were struggling to house thousands of evacuees as existing shelters were being used as coronavirus quarantine centres.

Extra shelters were being prepared in wholesale markets and government buildings with allowances made for social distancing, while masks and scarves were being distributed among the villagers.

Police in West Bengal state, which is expected to be badly affected by the storm, said people were unwilling to go to the shelters because they were afraid of contracting COVID-19 and many were refusing to leave their livestock behind.

‘We have literally had to force people out of their homes, make them wear masks and put them in government buildings,’ said a senior police official in West Bengal's capital, Kolkata.

Railway officials have diverted trains away from the cyclone's path to protect thousands of migrant workers travelling to eastern states from the capital New Delhi where they had lost their jobs due to the coronavirus lockdown.