On March 12 the government is expected to try again to get its deal approved, having sought extra assurances from the EU.
If a deal is not reached May will ask parliament on March 13 if it wants to leave without a deal.
If parliament rejects that outcome as well, mp’s will decide on March 14 if they want to try to delay Brexit, opening the door to a wholesale renegotiation, or a second referendum.
“This is the first time the public decided in a referendum something that was not what most members of parliament were in favour of – that is this challenge we’re having – this is the argument between government and parliament,” said Mark Harper, a former government minister.