An aviation firm has carried out the first tests in India of longer-range drone deliveries, as hopes grow that they could deliver medicines as well as Covid-19 vaccines to remote areas.

Lightning strikes killed 27 people and four passengers on a flight were hospitalised after severe turbulence during monsoon storms in eastern India, officials said Tuesday.

India on Wednesday reported a record 4,529 coronavirus deaths in a single day even as the number of new cases in its devastating new wave fell.

At least 21 people were dead and 96 were missing on Tuesday after a monster cyclone slammed into western India, compounding the misery for millions of others who are enduring a devastating coronavirus surge.

A major cyclone packing ferocious winds and threatening a destructive storm surge bore down on India on Monday, disrupting the country's response to its devastating Covid-19 outbreak.

India's coronavirus death toll surpassed 250,000 on Wednesday, official data showed, as the pandemic raged across the vast country of 1.3 billion people.

India's foreign minister Subrahmanyam Jaishankar, in Britain for G7 meetings, said on Wednesday he would hold his talks virtually after being exposed to possible coronavirus cases.

India released $6.7 billion in cheap financing for vaccine makers, hospitals and other health firms on Wednesday, to counter the devastating coronavirus surge gripping the country.

India's coronavirus caseload topped 20 million on Tuesday as it struggled to contain a huge outbreak, in stark contrast to gradual reopenings in the United States and Europe.

Rapid immunisation programmes in wealthier nations have helped suppress outbreaks, and the European Union was even looking at allowing vaccinated foreign tourists into the bloc as early as next month.

At least 16 Covid-19 patients and two nurses died Saturday in the latest in a series of hospital fires in India, officials said, as the country's health care system buckles under a surge in cases.