The Health Minister has voiced concern about the supply of medicines to Northern Ireland as a result of a Brexit regulatory barrier to securing stock from the rest of the UK.
Under the terms of the Brexit Withdrawal Agreement, Northern Ireland and Great Britain are to operate under different regulatory rules for medicines and medical devices.
A one-year grace period delaying the practical consequences of this is due to expire at the end of the year.
Northern Ireland currently secures 98% of its supplies from Great Britain.
Robin Swann told the Assembly's Health Committee that the EU's ill-fated attempt to suspend a part of the Northern Ireland Protocol in January amid a dispute over vaccine supplies had impacted efforts to prepare for the end of the grace period.
"It is something that concerns me and that's why we have been engaged quite significantly in regards to this," he said.
"Everyone thought that work was progressing well until the EU triggered Article 16 over vaccines - that unnerved people, that unsettled people and that has, I suppose, increased the level of concern that we're seeing, especially from the smaller and the more intricate suppliers of medicines and medical devices."
Robin Swann said solutions to the medical supply issue lay with ongoing negotiations between the UK and EU on longer-term resolutions to some of the problems created by the Protocol.
"It would be unacceptable that our medicines or medical devices are impacted and the supply of them," he said.
"We are a small part of the overall UK market in regards to many of these big pharma companies and I see no reason why we should be treated differently."
Mr Swann was asked about the issue by DUP committee member Jonathan Buckley.
Mr Buckley asked the minister to confirm that medical supplies would not have been an issue if the Brexit deal had resulted in Northern Ireland leaving the EU on the same terms as the rest of the UK.
"That is a political question and, from my point of view, as an Ulster Unionist health minister, I would agree, yes," Mr Swann replied.
The UK is pressing the EU to agree to a further year extension of the grace period on medicines and medical supplies.
Robin Swann says he would welcome any further extension.