Time is running out for U.K. Prime Minister Theresa May to get a deal done before Britain is officially supposed to leave the EU on March 29.
The lower house of the U.K. Parliament, the House of Commons, is scheduled to carry out a series of votes this week.
The first will be a second attempt at passing May's Brexit deal. If this fails again it will be followed by a vote on ruling out a no-deal scenario, and then a vote on whether the U.K. should seek to extend Britain's leaving date beyond the end of March.
May has already agreed a draft withdrawal deal with Brussels that sets the terms by which the U.K. leaves the bloc. Among other things this includes what money is owed, how citizens will be treated, as well as what happens at the land border between EU-member the Republic of Ireland and U.K.-ruled Northern Ireland.
However, the U.K. Parliament has to approve the terms and in the first "meaningful vote," back in January, lawmakers overwhelmingly rejected the 585-page treaty. Most of the dissatisfaction centered around a safety net arrangement known as the "Irish backstop."
The backstop is designed to ensure that should Britain and the EU fail to resolve their future trading arrangements, there can be no possibility of a physical border being erected within the island of Ireland.
It is hated by Euroskeptic lawmakers who fear it will trap the U.K. into a never-ending customs union with Europe. This is seen as the main reason May's deal failed at the first vote and efforts to overcome this are underway before a second meaningful vote is to be held.
Britain's top lawyer, Attorney General Geoffrey Cox, had visited Brussels in recent days to try to negotiate terms that will satisfy doubtful lawmakers but had little success. The EU has tried to reassure the U.K. that the backstop is a last-resort and could apply only to Northern Ireland, rather than the whole U.K. but that is also an unpalatable prospect for many British politicians.
May will hope to secure an extraordinary political comeback by persuading Parliament to back her deal at the second attempt. The first vote on January 15 was rejected by 432 votes to 202. The 230-vote margin of defeat was the worst for any government in modern U.K. Parliamentary history.
Only three lawmakers from the main opposition Labour party backed the plan but May was largely undone by the right-wing Euroskeptics within her own Conservative Party.
Key to May's hopes are that Europe and Cox can work up a tweak to the backstop that can persuade lawmakers within her party to reverse their vote. It is thought some may switch to support May out of fear that Brexit may not happen at all if they continue to reject her deal.
Partially causing that fear is a new move by Labour to call for a second referendum. The left-of-center opposition has so far played its Brexit hand closely, recognizing that large parts of Britain that often vote for Labour also voted to leave the EU.
However, now it says it will put forward an amendment to May's deal, calling for a fresh referendum on Britain's future relationship with mainland Europe. The fresh questions that Labour want lawmakers to answer are not yet known.
An approval of the deal on Tuesday is expected to cause a surge in sterling after months, if not years, of uncertainty for markets.
If Tuesday's vote is rejected then on Wednesday lawmakers will be asked if Britain should take a no-deal Brexit option off the table in its negotiations.
Businesses, regional governments and pro-EU analysts have all warned that leaving the European Union with no deal on trading arrangements could cause huge disruption and lead to a negative economic impact.
Media reports have warned of food and medicine shortages, as well as massive delays at the border for both people and goods.
Several firms have cautioned on the impact on production and this week auto giants Toyota and BMW both said a no-deal Brexit threatened their U.K. operations.
A small but influential element of May's Conservative Party have rejected much of this concern as bluster and fear-mongering, arguing that a no-deal Brexit would in fact represent the closest representation of what the British people voted for.
Previous indicative votes have suggested that Parliament will vote to rule out leaving without a deal, but the strength of this vote's outcome has already been questioned. Meaning, it would not completely rule out the possibility of a no deal still occurring.
By the time of this vote there will be just 15 days left until the U.K. officially exits the European Union.
May has said that if Parliament rejects both her deal and subsequently, no deal, then the U.K. could ask for more time and seek from Brussels a "short limited extension" to the negotiating period prior to leaving.
Placing an extension option on the table is seen by some as putting more pressure on members of the Conservative Party to back May's current deal. By pushing out the exit date, lawmakers within Parliament may be able to gain momentum toward a softer Brexit or even a second referendum — something that Euroskeptics would be keen to avoid.
May has warned that any extension should not go beyond June, otherwise the U.K. would need to take part in elections to the new European Parliament.
Even if May's deal is approved, she herself may push for an extension. The U.K. needs to approve a large amount of legislation associated with the withdrawal deal and lawmakers reportedly do not have enough time to get the bill into law.
Both London and Brussels have agreed to end negotiations by this summit, just one week before the official Brexit date.
It's expected that if the U.K. can agree terms with Brussels prior to this date, then the 27 country leaders of the European Union will officially sign off on Britain's departure.