Filming of blockbusters such as Game Of Thrones and Star Wars in Northern Ireland and the Republic could be hit by Brexit, business leaders said.
Tax barriers could hamper production companies assembling props or using airports on one side of the border then travelling to the other side. Athletes representing Ireland on an all-island basis may need travel visas, the Institute of Directors (IoD) suggested.
Game of Thrones is a hugely successful series filmed partly at locations around Northern Ireland. Stormont agency NI Screen helped fund the HBO production. Star Wars was partly shot on Skellig Michael, Kerry and Malin Head in Donegal. An IoD report said Brexit could make administrative obstacles for the creative industries.
The report said: "This could create significant problems for the 250 cross-border movie, television and radio companies who are currently part of a thriving all-Ireland industry."
The cast flew into Belfast ahead of filming at Malin Head. Brexit could complicate similar arrangements in future, according to the review's author Seamus Nevin.
He said there could be difficulties surrounding cross-border licensing as well as tax implications. Freedom of movement will be one of the focuses of Brexit negotiations.
British business leaders have teamed up with their Irish counterparts to urge politicians to make maintaining a strong trading relationship between the two countries a high priority in the talks.
A new report - The Irish Question: Brexit, Business And The Future Of UK-Ireland Relations - for the first time combines surveys from the Institute of Directors in the UK and IoD Ireland.
It said: "With the exception of football, all sports are organised on an all-Ireland basis and have a single national representative team. If the above issues are not resolved, athletes representing Ireland may require travel visas to represent their own country in sport.
"Both the UK and Irish governments have said they plan to revert to the Common Travel Area (CTA). However, this is not cut-and-dried as the EU seeks to prohibit third-party states from giving the citizens of one EU member state preferential treatment."
The results of the business leaders study highlight the deep economic links between the two countries, with a third of the UK companies questioned, and three-quarters of Irish firms, doing business across the border.