Dhaka, Nov. 26 -- Global authorities reacted with alarm on Friday to a new coronavirus variant detected in South Africa, with the EU and Britain among those tightening border controls as researchers sought to find out if the mutation was vaccine-resistant.

Hours after Britain banned flights from South Africa and neighbouring countries and asked travellers returning from there to quarantine, the World Health Organization (WHO) cautioned against hasty measures.

One South African scientist expert labelled London's decision a symptom of "vaccine apartheid", though European Commission chief Ursula von der Leyen said the EU also aimed to halt air travel from the region and several other countries including India, Japan and Israel toughened cu...