The “backstop” plan was agreed by negotiators between the UK and the EU and was part of Theresa May`s withdrawal deal in November 2018 (often referred to as the Brexit “divorce deal”). On 10 October 2019, Mr Johnson and Leo Varadkar held “very positive and promising” talks that led to the resumption of negotiations and a week later Mr Johnson and Jean-Claude Juncker announced that they had agreed (subject to ratification) on a new withdrawal agreement replacing the backstop with a new protocol on Northern Ireland.2  In July 2019, Theresa May resigned and Boris Johnson became Prime Minister, boris Johnson saying he wanted to replace the Irish backstop as part of the withdrawal agreement.  On 19 August, in a letter to the President of the European Council, the Prime Minister declared that the agreement was “undemocratic and incompatible with the sovereignty of the United Kingdom”.  He stressed that this was “not compatible with the UK`s desired end goal” for its relations with the EU. Its third reason for the unsurability of the backstop is that it “weakens” the Good Friday Agreement and the peace process in Northern Ireland. Tusk said opponents of the deal, without “realistic alternatives,” supported the re-establishment of a hard border on the island of Ireland. That`s the reality, “even if they don`t admit it,” he added. “The backstop is an insurance to avoid a hard border on the island of Ireland, unless an alternative is found,” Tusk tweeted.  The Irish Government considered that “the real objective of the backstop was to maintain the status quo by guaranteeing freedom of movement and not a hard border on the island of Ireland; which is of paramount importance to the GFA. The reality is that Brexit is a threat to the GFA.  In the months that followed, the British Parliament refused three times to ratify the agreement.
In July 2019, Boris Johnson became Prime Minister of the United Kingdom and leader of the Conservative Party. On 28 August 2019, the Johnson government refused to negotiate with Brussels unless the backstop was abolished, which the EU did not say.  The backstop became a sensitive point when Theresa May tried to convince Parliament to support the withdrawal agreement she had negotiated. The Irish backstop has been highly controversial among some MEPs and is one of the main reasons why the withdrawal agreement has not yet been adopted by Parliament. New Prime Minister Boris Johnson now says the backstop is “dead.” The rest of this piece explains how the political situation around the backstop has evolved over time and why the Irish border is an important subject. Boris Johnson opposed the backstop and said it was undemocratic and could trap the UK in EU customs territory. The “backstop” would have required northern Ireland to remain in certain aspects of the internal market until an alternative agreement between the EU and the UK is concluded. The proposal also provided that the UK as a whole would have a common customs territory with the EU until a solution was found to avoid the need for customs controls in the UK (between Northern Ireland and Great Britain).
The “backstop” element was that if the UK and the EU did not agree on another agreement, for example on a trade agreement between the UK and the EU at the end of the transition period, the agreement could continue to apply indefinitely. It seems unlikely that the EU will sign a withdrawal agreement that does not include the Irish backstop or anything very similar. He says we need to find an alternative to backstop, and last week German Chancellor Angela Merkel gave him 30 days. Paul Bew, a Crossbench peer, noted that the downward nature of the backstop reverses the ascendancy of the Good Friday Agreement, risking “the current deterioration of North-South relations increasing in unpredictable and dangerous ways.”  In the event that the backstop was to enter into force, Northern Ireland remained a member of the internal market until a trade agreement was reached to keep the border virtually invisible.