It's the second-highest warning category in the department's five-point scale for travel advice.
In a statement, Minister for Foreign Affairs Charlie Flanagan says they're encouraging any Irish visitors to Tunisia to review whether their presence there is essential, and if it's not, to leave the country.
However he says the department believes there are relatively few Irish visitors currently in Tunisia, after the decision by travel companies to discontinue direct flights from Dublin to Monastir earlier this month.
Three Irish people were among the 38 shot dead in a terrorist attack on a beach in Sousse two weeks ago.
