Following Brexit, the border between Northern Ireland and the Republic of Ireland will become an external EU border. In theory a “hard” border could return, with both fewer and supervised crossing posts, to support the necessary customs infrastructure. Both EU and UK negotiating teams have made clear that this outcome would not be acceptable in any final exit agreement. In order to keep a friction-less border, the European Union proposed a “backstop agreement” within the Withdrawal Agreement called the Northern Ireland Protocol. This would come into force only if there were no other solutions at the time, and thus Northern Ireland would continue to operate some EU Single Market rules and remain within the EU Customs Union, for as long as may be necessary to avoid the need for border checks. Although the British government agreed with the principle of such a backstop at the December 2017 meeting, it rejected the legal text prepared by Michel Barnier’s office because it created a legal and regulatory barrier between Northern Ireland and Great Britain. The British side asserts that Northern Ireland cannot be treated differently from any other part of the United Kingdom.

On 15 January 2019, the UK parliament rejected a government motion to approve its draft withdrawal agreement. As of late January 2019 many Brexit-supporting Conservative and DUP MPs continued to oppose a backstop without a specified end-date, concerned that it could tie the UK to many EU rules indefinitely. This opposition was in spite of a LucidTalk opinion poll (released 6 December 2018) indicating that 65% of Northern Ireland voters were in favour of a Brexit that kept Northern Ireland in the EU single market and customs union.[46] On 28 January 2019, May expressed opposition to the backstop that she and the EU had agreed and urged Tory MPs to back a backbench amendment replacing the backstop with unspecified “alternative arrangements”. On 29 January, this proposal, which was presented by MP Graham Brady, passed in the House of Commons by a margin of 317 votes to 301 votes.

A “meaningful vote” is a vote under section 13 (2) of the European Union (Withdrawal) Act 2018, requiring the government to arrange for a motion proposing approval of the outcome of negotiations with the EU to be debated and voted on by the House of Commons before the European Parliament decides whether it consents to the withdrawal agreement being concluded on behalf of the EU in accordance with Article 50(2) of the Treaty on European Union. Theresa May’s led parliament have proposed three meaningful votes to the house of common but have failed on every occasion.

Parliament voted on this Withdrawal Agreement on Tuesday, January 15, 2019. Members of Parliament voted 432-202 to reject the agreement, the biggest defeat for a government in the House of Commons in recent history.Theresa May survived a no-confidence vote held on January 16 and she unveiled her Plan B on January 21. The plan was criticized for being very similar to the original deal she presented. On January 29, MPs voted for May to return to Brussels to remove the controversial Irish backstop portion of her plan and replace it with alternative arrangements, but the EU had said the deal is not open for re-negotiation. The backstop is a plan to avoid a hard Irish border if the U.K. and EU don’t sign a free trade deal during the transition period post-Brexit. May was seeking changes to the controversial Irish backstop provision to win Parliament’s backing. The backstop is intended to be temporary, but Euroskeptic MPs worry it will last indefinitely and compromise Britain’s autonomy. She was also accused by the Labor Party of “recklessly running down the clock” to force MPs to choose between her deal and a no deal outcome.

MPs voted against her deal by 391-242 votes on March 12 despite May’s claim of “legally binding” changes to the agreement, setting Britain on the path to a no-deal Brexit. Parliament stepped in to delay it and the EU gave its permission. On March 27, none of the eight Brexit alternatives voted on by Members of Parliament received a majority. May’s deal was rejected again on March 29 by a margin of 58 votes, despite her vow to resign before the next stage of negotiations if it was passed.
The House of Common on 2nd April, voted against a no deal Brexit, placing more pressure on Prime Minister Theresa May to pull support for her deal. Theresa May successfully requested for an extension of time till the 12th of April with a condition that no extension of time will be granted if the UK does not come up with a deal. In a bid to succor the situation, Theresa May has resort to working with Labour opposition leader, Jeremy Corbyn. The media reports that talks have been progressive with the opposition leader but it has not been conclusive.