Ian Paisley says EU officials should build a hard border themselves if they are insistent Northern Ireland remaining in the customs union is the only way to maintain the "frictionless" operations.
The Guardian reports the UK negotiating team has been warned the EU draft withdrawal agreement will say that Northern Ireland will remain in the customs union and single market after Brexit in order to avoid a hard border.
It suggests Northern Ireland will remain under EU law after the transition period where it is relevant to the north-south economy, and the requirements of the Good Friday Agreement.
If it goes ahead it is likely to provoke disagreement between the EU and UK negotiating teams, as well as create issues between the DUP and the Conservative Party. The two have a confidence and supply deal which allows Theresa May to run a minority government.
However, British officials negotiating in Brussels have been told by their counterparts there could be a “sunset clause” which could void the clause in the event of a generous free trade agreement or a technological solution that could be as effective as the current arrangements.
The draft agreement is expected to be published in around two weeks.
The Guardian reports the UK is expected by Brussels to sign off on the text which will see Northern Ireland remain under EU law at the end of the 21-month transition period, wherever it is relevant to the north-south economy, and the requirements of the Good Friday Agreement.
The UK government’s position on seeking to leave the customs union and the single market and yet wanting frictionless trade, it's claimed, presents a danger to trade and peace in Northern Ireland.
Responding to a tweet by a BBC journalist about the Guardian's story, DUP MP Ian Paisley said: "So Barnier calls for hard border. Let [sic] him erect it!"