Australia will reduce the number of its citizens able to return from India and other red-zone countries to contain the risk of more virulent strains of Covid-19 spreading, the government said as it announced changes in its vaccination programme.

The restrictions will result in a 30 per cent reduction in direct flights from India to Sydney and chartered flights that land in the Northern Territory, according to Reuters.

Prime Minister Scott Morrison, speaking to reporters after a meeting of the National Cabinet, said that he would announce in the next 24 hours when the new restrictions would come into place.

Australia currently allows about 5,800 citizens or permanent residents to enter its territory each week before quarantining for two weeks in hotels. It is not clear how many of these are typically from India each week.