FILE PHOTO: EU Chief Brexit Negotiator Michel Barnier attends a joint news conference with Austrian Chancellor Sebastian Kurz in Vienna, Austria February 28, 2019. REUTERS/Leonhard Foeger

BELFAST (Reuters) - Proposals from the European Union’s chief Brexit negotiator Michel Barnier that would give Britain the unilateral right to leave the customs union are a “non-starter”, a Sky News reporter cited sources in the Democratic Unionist party as saying on Friday.

Sky Northern Ireland correspondent David Blevins quoted DUP sources in a Twitter post as saying the Barnier proposal showed “no respect to the constitutional and economic integrity of the United Kingdom. It’s a non-starter.”