Sri Lanka has banned face-covering clothing, after suicide attacks killed 250 people and injured hundreds more on Easter Sunday.
The emergency law, imposed by President Maithripala Sirisena, will assist security forces in finding remaining attackers, eight days after Islamist militants targeted churches and hotels.
From Monday, any face garment which "hinders identification" is banned to ensure national security.
The niqab and burka - both worn by Muslim women - were not specifically named, but the move is reportedly seen as taking aim at the garments.
The emergency law comes after a Sri Lankan MP proposed a ban on women wearing the burqa, arguing it should be forbidden on security grounds.
Just under 10 per cent of people in Sri Lanka are Muslim, but only a small number of women are thought to wear the face-covering niqab, or the burka, a one-piece veil that covers the face and body.
A spokesman for President Maithripala Sirisena named Dharmasri Bandara Ekanayake told Reuters: "It is a presidential order to ban any dress covering faces with immediate effect."
Prime Minister Ranil Wickremesinghe, who is feuding with Sirisena, also sent out a separate statement claiming that he had asked the justice minister to draft regulations. However, there are concerns that if the ban goes on for a long period of time, it could fuel tensions in the religiously-diverse area.
Human Rights Watch condemned the ban, with the group’s executive director Kenneth Roth tweeting: "That needless restriction means that Muslim women whose practice leads them to cover up now won’t be able to leave home."
Meanwhile, the All Ceylon Jamiyyathul Ulama (ACJU) - the top body of Islamic scholars in Sri Lanka - stated they supported a short-term ban on the basis of security, but objected against any attempt to legislate against burqas.
"We have given guidance to the Muslim women to not to cover their faces in this emergency situation," ACJU assistant manager Farhan Faris said. "If you make it a law, people will become emotional and this will bring another bad impact ... it is their religious right."
Islamic State claimed responsibility for the attacks, but police suspect the bombings were also carried out by two local Islamist groups: National Thawheed Jammath - established by the alleged organiser of the incident, Zahran Hashim Zahran - and Jammiyathul Millathu Ibrahim.
On Friday, the father and two brothers of Hashim were killed in an operation by security forces. Around 10,000 soldiers have been deployed around the island as the authorities hunt for more suspects.