The British Government remains committed to leaving the EU Customs Union according to sources in Downing Street.
British Prime Minster Theresa May is refusing to back down on the commitment – despite a significant defeat in the House of Lords over the issue and rumours that her position may be softening.
Peers voted on Wednesday in favour of an amendment to the flagship EU Withdrawal Bill which would seek to maintain the possibility that Britain might stay in a form of customs union.
She faces further political conflict over the issue this week ahead of a vote in the House of Commons.
The trade and customs bill will be debated by MPs on Thursday with a vote that, while not binding, will be seen as an important indicator of the parliamentary mood.
Amendments to the bill were tabled by MPs Anna Soubry and Chuka Umunna, who tweeted "the Brextremists threaten May with a leadership election if she concedes on the customs union."
Mrs May is against remaining in the customs union, and has pledged that the UK will not be part of the bloc's single market after Brexit.
But she faces criticism both from those who wish to take a softer line and from the hard Brexiteers in her own party.
Brexiteers are expected to tell the PM that the proposed customs partnership - an arrangement that would see the UK collect import tariffs on behalf of Brussels - would be unworkable.
Boris Johnson, David Davis and Liam Fox may put pressure on the PM to abandon the customs union, according to The Times newspaper, which reported the trio feared Mrs May's preferred option would encourage Brussels to push for retaining it.
Housing and Communities Secretary Sajid Javid echoed the sentiments on Sunday, tweeting that leaving the customs union was an "intrinsic part" of leaving the EU.
"Some see the CU as some kind of post-Brexit comfort blanket," he said. "But they're only thinking about the past referendum, not the UK's future."
Some see the CU as some kind of post-Brexit comfort blanket. But they're only thinking about the past referendum, not the UK's future. Let's look forwards with confidence.
— Sajid Javid (@sajidjavid) April 22, 2018
He is one of many vocal Tory MPs, including Michael Gove, opposing any softening of a withdrawal from the customs union.
Former Cabinet minister John Whittingdale reiterated a commitment to leaving the customs union.
"Part of the problem is that there are some in the European Union and in the Irish Republic who want to make out that we have to stay in the customs union and will not examine other alternatives," he said.
"And votes like ones in the House of Lords are going to add to the view over there that somehow the British Government might u-turn or go back."
CBI head Paul Drechsler, however, has rebuked those lobbying for a hard departure from the customs union.
Replying to Mr Javid's tweet, he suggested MPs should "rise above ideology and lead based of fact, analysis and evidence - all of which favours a customs union."
An MP of your talent should rise above ideology and lead based of fact, analysis and evidence - all of which favours a customs union. Always happy to discuss,
— Paul Drechsler (@drechsler_paul) April 22, 2018
