With exit just a year away, how did we get to this point?
Brexit is due to happen on March 29, 2019 - yes, that is just over one year away.
Britain has been an EU member for 44 years, and now it must extricate itself from a club in which it has shaped the laws, values and trade deals for the best part of the last century and all of this one.
The UK says it still wants to trade with the EU - after all, the EU represents 44pc of the UK's export market. And the EU is the largest and richest market in the world.
But in order to negotiate a trade deal, the EU said that the UK must deal with three "divorce" issues before the talks on trade can begin.
These include how much the UK owes the EU - like all 28 member states, it has monetary commitments to the EU budget.
Also, what happens to UK citizens living elsewhere in the EU and EU citizens living in UK; and, crucially, how Britain proposes to live up to its legal obligations to the Good Friday Agreement - and ensure there are no borders between Northern Ireland and the Irish State.
So far, the UK has not given any solutions as to how it proposes to prevent the hard Border.
As a result, last December, the EU and UK created a "backstop solution", or worst-case scenario.
The backstop would mean that in order for there to be no Border on the island of Ireland, the North would have to abide by EU rules and regulations.
This is to ensure goods of a lower standard coming from a non-EU state (the UK) don't end up in an EU member state (Ireland). Theresa May agreed to this backstop last December - but this week appears to have reneged on it.
Also in mid-negotiation are talks on a so-called "transition period".
This is a limited period from March 2019 until December 2020 in which the UK has some time to adjust to the new post-Brexit rules with the EU.
During this time, Britain will still have access to the EU single market and customs union, but as it will be no longer be an EU member, it loses its right to vote on EU laws, rules or trade deals.
The EU says that for this time, and so long as Britain is in transition and therefore has the privileges of EU membership, it has to continue to be subject to all EU laws and principles such as freedom of movement.
However, there is further objection to this from Brexiteers.