The Bangladesh government has extended the quarantine period to 7 days, from previously fixed 4 days, for the incoming passengers from London, UK.
The new measure will come into effect immediately, said a notice issued by Biman Bangladesh.
Authorities took the decision hours after latest evidence suggests the new variant of coronavirus that has emerged in the UK may be more deadly.
The data about the new strain has been assessed by scientists on the New and Emerging Respiratory Virus Threats Advisory Group, which has briefed the government, BBC reports.
However, all the evidence remains at a preliminary stage. Studies have already shown it can spread more easily than another version of the virus.
The new variant was first detected in Kent in September. It has since become the dominant version of the virus in England and Northern Ireland and has spread to more than 50 other countries.