Covid-19: 'Please respect me and wear your face covering' - CMO
Chief medical officer Sir Michael Mc Bride says it "upsets" and "frustrates" him when he sees people not wearing a face covering "who clearly don't have an underlying health problem".
He told BBC NI's The View Programme that he challenges those people.
It comes as Justice Minister Naomi Long warned that police will take enforcement action against people in Northern Ireland who abuse staff in shops, bars and restaurants over Covid restrictions.
The justice minister acknowledged there would continue to be "challenges" in enforcing the laws.
Fewer than 10 fines have been issued to people in Northern Ireland for breaching rules on face coverings since the laws took effect in July 2020.
Mrs Long said it was not an issue solely for her department to manage.
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