Selwyn Stein, CEO of VAT IT Reclaim, said he was currently trying to advise clients on how they could navigate moving goods between the UK and EU via Northern Ireland in the event that the current situation changes.
“There are still tonnes of problems with every trade agreement,” he told the audience at the Evening Standard’s SME XPO in London on Wednesday.
“Northern Ireland is obviously front and centre at the moment, and the geopolitical issues that arise in the back of it.
“If there are any potential problems with that and there’s some form of trade war, then the benefits of the [existing] free trade agreement could potentially fall away.
“It’s a mess at the moment.”
The government wants to introduce a law which will override the Brexit deal it signed on Northern Ireland, which critics say threatens the Good Friday Agreement.
Because Northern Ireland is the only part of the UK with a land border with an European Union country - the Republic of Ireland - it needed special trading arrangements when the UK left the EU.
At present, goods and documents are inspected at the border between Northern Ireland and Great Britain, at Northern Irish ports.
But unionist parties say that placing an effective border in the Irish Sea undermines Northern Ireland’s place within the UK.
“I’ve been helping them explore alternatives depending on whether the existing deal remains or is replaced,” Stein said.
“There are lots of different routes [for exports] which go via mainland Europe or Ireland depending on what people’s priorities are.”
He said businesses could send goods via the Netherlands or France to circumvent difficulties moving goods between Ireland and Great Britain.