The NI executive should urgently reconsider its policy on face masks in stores, Health Minister Robin Swann said.
Mr Swann said there is a “perception – right or wrong” of mixed messages, which needs to be clarified.
Face masks are strongly encouraged in stores in Northern Ireland, but are not required.
The NI executive is due to review the policy on August 20 and may legislate it on that date.
Face masks in shops are mandatory in England and Scotland, but not in Wales.
Ministers are looking for a compliance rate of between 70% and 80% and could apply face masks if public participation falls below that level.
However, in a letter sent to fellow management on Sunday and seen by BBC News NI, Mr Swann requested that the review date be moved forward to August 13.
The health minister said he was not convinced the advice would be heard and he wanted the executive to warn the public that if they don’t listen, the policy will be enforced “in the next few days.”
He added that the current policy is seen by some as “vague and confusing”.
“While the executive is united on the need to cover their faces, there have been differences of opinion on how best to achieve this,” he wrote.
“This led to the adoption of a compromise position by the executive last month.
“While some may view this position as nuanced and graduated, others have described it as vague and confusing. “
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He added that “the wording of the decision had been the subject of different interpretations” and that “the ambiguity did not prove to be constructive”.
Mr Swann said that “the message will be much more effective if it is supported by a clear and collective signal of intent on the binding issue”.
The health minister also said the policy review date should be brought forward from Aug. 20 to Aug. 13, with an “expected start date for application” the following day.
He signed the letter suggesting that they “still have time to clear up any confusion and put forward a concise position.”
Mr Swann has previously said he was not convinced that enough people would wear face masks in stores without an app item.