Speaking on the BBC's Andrew Marr Show, British Brexit Secretary David Davis has said that the UK government wants to have an "invisible" border with the Republic of Ireland. Video: Reuters

British government Brexit Secretary David Davis has suggested “tagging of containers” could be one method of monitoring trade across the Border after Britain leaves the EU.

Speaking on the BBC’s Andrew Marr show on Sunday morning Mr Davis said the British government wants to maintain an “invisible border” in Ireland and that work on how this can be done must start now.

“It’s technically difficult but doable,” he said. “We want to have effectively an invisible border between the north and south. “Now there are technical ways of doing that, number plate recognition on vehicles, tagging of containers, trusted trailer schemes — quite a lot of very technical stuff.”

Negotiations between the Conservative Party and the DUP over a confidence and supply agreement with Theresa May’s government at Westminster are expected to draw to a close this week, ahead of the vote on the Queen’s Speech on Thursday.

The DUP denies this and on Sunday deputy leader Nigel Dodds also rejected suggestions by Britain’s Green Party leader Caroline Lucas that his party is full of “dinosaurs” over its stance on environmental and rights issues.

He told Sky News: “People can always go back through the archives of any political party and find individuals saying things or policies from 20, 30 years ago.

“But they need to read our manifesto and look at the recent years in Northern Ireland where the DUP has been the main partner in government with republicans to move this province forward.”

Mr Dodds, who along with DUP chief whip Sir Jeffrey Donaldson have been the main negotiators with Downing Street, said those in Britain who hold different views on social issues like same sex marriage and abortion have no reason to fear the Northern party’s influence there. He said “cultural and social issues” are devolved matters and that his party will not be involving itself in this at Westminster.

“Nobody has anything to worry about in that,” he said. Speaking at the weekend to Bloomberg former US Senator and Northern peace talks envoy George Mitchell said he respected Brexit is a democratically taken decision but described it a “self inflicted wound” and something that would “devastate the Irish economy”.

Mr Mitchell said: “Peace is never certain particularly in areas that have been by plagued by long standing conflicts, such as Northern Ireland, and while I am pleased the agreement we reached 19 years ago has largely held, violence is minimal now and the border is open, where before it was tightly controlled border, I think there is risk.”

On whether he believed the British government was sufficiently aware of the risks Northern Ireland could be exposed to by Brexit he said he didn’t know how much they thought about it before the vote “but it really is a problem now”.