A customs union between Ireland and Northern Ireland must survive Brexit for the good of the economy, the UK shadow chancellor John McDonnell has said.
Mr McDonnell from the British Labour Party said that "discussions should be had" about preserving an open union between the North and the South after the UK's exit from the EU.
Mr McDonnell, speaking on the Andrew Marr Show, said: "Bringing back a hard border I think would be a nightmare, I think it would not be practical anyway.
"We have to have a relationship which is as close to the customs union.
"I would not want to see anything that undermines the peace process in particular and all the gains that we have had."
He added: "We are not saying the customs union, we're saying a customs union and that's a discussion that should be had."
When pushed on whether there should be a "unique arrangement" over a customs union, he said: "I think that's part of the discussions that need to take place."
He said the key issue is to ensure there is no arrangement that could "damage the economy North and South" or undermine the results of the peace process.