Sri Lanka has banned face coverings in public, following a spate of suicide attacks on Easter Sunday that killed at least 250 people and injured hundreds.
President Maithripala Sirisena said he was using an emergency law to impose the restriction from Monday.
Any face garment which hinders identification will be banned to ensure national security.
The niqab and burka worn by Muslim women were not specifically named.
The move is perceived as targeting the garments, however.
Sri Lanka remains on high alert eight days after Islamist attacks that hit churches and hotels.
Dozens of suspects have been arrested, but local officials warned that more militants remained at large.