AS many as 100,000 British firms have taken steps to register companies in the Republic of Ireland in the wake of the Brexit vote.
Stephen Kelly, chief executive of campaigning organisation Manufacturing Northern Ireland, told a House of Commons committee that the companies would be used in the event of a “hard Brexit” and a serious loss of business due to punitive tariffs imposed by the EU on Britain.
At the moment, many are merely dormant companies.
"Obviously this is a sensitive issue, as the relocation of a company, or even part of it, could have serious implications for jobs," Mr Kelly said.
"My understanding is that the type of companies involved range across the board, from manufacturing business to legal and financial services."
In the banking sector, Barclays is preparing to expand its Dublin operation because of Brexit.
It is believed many other banking firms in the City of London are following a similar course and eyeing up premises in Ireland.
The attractions of Ireland are numerous, including access to the European market, a favourable tax regime and a skilled English-speaking workforce.
One Northern Irish company has made it plans public.
“Almac, a very successful pharmaceutical company based in Craigavon, made plans the very morning after the result of the Brexit referendum was known.
"They needed an EU presence to satisfy customers. And so opened a facility in Dundalk," Stephen Kelly told The Irish Post.
Almac employs around 2,600 people in Craigavon; the new facility in Dundalk will initially employ 100 people.
In the meantime, the manufacturing part of the business will stay in Co. Armagh, and the new facility brought into play when circumstances are clearer.
Like most companies, the movies is a safety net, according to Mr Kelly.
"Ireland could benefit being so close to a major trading area that is outside the EU, and the North would be an integral part of such a beneficial situation," Mr Kelly said.