A person was refused permission to board a flight from Dublin to the US as a result of the travel ban on people from Iran, Iraq, Syria, Sudan, Libya, Yemen and Somalia.
While the Department of Transport would not comment on the circumstances of the case, a spokesperson confirmed that in such cases An Garda Síochána is notified.
"If the person is an Irish national or a non-Irish national legally resident in the State, a criminal history check is done and if they are not wanted for any crime or warrants, etc, they are escorted to landside," the department said.
In a letter to the Taoiseach seen by Independent.ie, Independent TD Katherine Zappone warned the travel ban could "have legal implications for Ireland".
Meanwhile, the Foreign Affairs Minister said the fast-tracking of US-bound passengers through Dublin and Shannon airports must be maintained despite Donald Trump's 'Muslim ban'.
As the Government scrambled to come up with an appropriate response to Mr Trump's new immigration policy, Taoiseach Enda Kenny ordered an immediate review of pre-clearance visa arrangements.
However, writing in today's Irish Independent, Foreign Affairs Minister Charlie Flanagan says this is not the time "to place a question mark over the continued operation of the US pre-clearance facilities".
"Many other countries envy the pre-clearance arrangements our citizens enjoy. I believe we should maintain them," he says.
Children's Minister Katherine Zappone said the Government should be prepared to eject US immigration officials from our airports if a review finds that Mr Trump's policies breach equality law here.
The pre-clearance facility, which has been in place since 2008, was used by 1.18 million people in Dublin last year and by 204,000 people in Shannon.
The rules ensure that travellers departing Ireland are treated in the same way as domestic passengers once they enter the US.
Members of Cabinet were yesterday circulated a memo by Transport Minister Shane Ross who warned against changes to the US pre-clearance rules.
"It would be premature to contemplate a change in these arrangements before obtaining greater clarity on this administration's immigration policy," the memo states.
But in a letter to the Taoiseach, seen by the Irish Independent, Ms Zappone took an entirely different approach.
The Independent TD warned the application of the travel ban could have legal implications for Ireland and urged the Taoiseach to "take a stand for equality, human rights, and the rule of law in the face of contemporary developments in the United States".
"I am deeply concerned that the application of the executive order by pre-clearance officers in these areas, assisted by gardaí and customs and excise officers, is resulting in people experiencing discrimination based on religion and nationality within our jurisdiction.
"I also wish to express my concerns about the implications of this executive order for Irish citizens who hold dual citizenship with listed states, including those who were born there. It is not possible effectively to rescind citizenship in a number of these states: Iran, Syria, Libya and Yemen," Ms Zappone said.
Fellow Independent minister Denis Naughten is understood to be backing Ms Zappone's level of concern.
"Mr Naughten abhors any discrimination on religious grounds," a source said.
Mr Kenny said the review is necessary "so that we can be absolutely clear of the importance of this".
Ireland's relationship with the United States dates back to before the independence of either country. It is built on the hundreds of thousands of our people who left for a new life in the US, whether fleeing famine or conflict at home or seeking better economic opportunity.
Acting Attorney General Sally Yates, a Democratic appointee, last night directed Justice Department attorneys not to defend President Donald Trump's controversial executive refugee and immigration ban, declaring that she was not convinced the order was lawful.