Britain will leave the customs union after Brexit, Downing Street has insisted, with Theresa May and other ministers set to skip a Labour bid in the House of Commons to stop the UK leaving later this week.

The Government moved to reassure Eurosceptic tory MPs after weekend reports that Mrs May’s team had privately concluded that the UK could have to remain in the customs union after all.

Civil servants on Britain’s negotiating team are said to favour keeping Britain in a customs’ union to avoid having to construct a post-Brexit hard border between northern and southern Ireland.