They said: "Given the current number of new cases in Donegal and neighbouring areas of Northern Ireland in Derry, Strabane and Fermanagh we would appeal to everyone to avoid all but necessary travel across the border".
(Alliance News) - The Irish Government has announced plans to tighten its coronavirus restrictions in Donegal.
Level 3 restrictions come into place for Donegal at midnight tonight.
At a meeting of the National Public Health Emergency Team in late August, health officials discussed how pubs and bars "pose a particular risk to the spread of Covid-19 as alcohol can have a disinhibiting effect on people and impair judgement".
However, wet pubs will be allowed to remain open under the same guidance, which differs from the Dublin restrictions.
Mr Martin said today: "I spoke to Arlene Foster yesterday evening and Michelle O'Neill and I did indicate that on a practical level, it would make sense if we could harmonise as closely as possible respective public health measures".
Six visitors from one other household will be permitted into a private home. From Monday weddings can have a maximum of 25 guests only.
The rest of the restrictions for Donegal can be viewed here. Three further deaths due to the virus were reported.
Of today's cases, 21 are in Galway, the fourth highest level behind Dublin (152), Cork (32), and Donegal (22).
Of the new cases, 162 are men and 152 are women; 69% are under 45; 33% are associated with outbreaks or are close contacts; and 49 cases are community transmission.
Donegal's 14-day incidence rate is now higher than Dublin's, with 148.2 positive cases per 100,000 population, and Dublin recording 144.5 positive cases per 100,000.
People in these areas are being urged to follow public health advice and Taoiseach Micheál Martin has said 'to be honest, we could have similar announcements for other areas in the coming week, if the numbers keep rising.' His announcement about placing Donegal into level 3 can be viewed below.
He said the decision had been made "in an effort to protect you and to prevent a further deterioration in the situation there".