1,000 Irish families who provide holidays for children whose health has been affected by the Chernobyl nuclear accident have been told that future trips have been banned.
The Department of Foreign Affairs says it is having talks with the Belarusian authorities to try to establish why the ban has been imposed and to see if it can be lifted.
The travel ban which initially applied to the US has now been extended worldwide, although the government in Italy has made a special agreement with Belarus to allow holiday visits to continue there.
The Dept of Foreign Affairs says it is aware of the situation and embassy staff in Moscow are in discussions with the Belarusian authorities to try to establish why the ban has been announced and to see if it can be lifted.
Chernobyl Children's Project CEO Adi Roche described the announcement by the Government of Belarus as 'shocking news'.
Ms Roche, who is to meet minister Minister Martin Cullen on Monday, says failure to have the issue resolved would be a disaster for the children.
She told RTÉ News that the twice-yearly trips to Ireland were vitally important for the children's health and also allowed them to visit medical specialists and receive treatment.
She has appealed to the Government to work to have the ban reversed.