More than 40 Australians due to leave India on the first repatriation flight in two weeks have tested positive to COVID-19.

Close contacts of people who tested positive will also be unable to fly, which means a total of 70 people can no longer fly home.

There were 150 Australians booked on the flight from New Delhi.

The positive diagnoses mean they will be stuck in India until they recover.

Meanwhile, a plane carrying medical supplies has left Darwin bound for the subcontinent.

Another 4,000 people have died from COVID-19 in India over the past 24 hours.