There are some, particularly those from opposition parties, who believe a fresh negotiation between the EU and U.K. is still possible.
Britain and Northern Ireland are set to leave the European Union in less than three months and so any attempt at major surgery to the existing deal would likely require more time.
That would mean an extension of Article 50 which is the legal means by which a country leaves the Union. May's triggering of the clause in March 2017 set off a two-year countdown to Britain's exit on March 29.
The chief investment officer at Barclays Investment Solutions, William Hobbs, told CNBC Monday that currency traders had recently raised bets on an extension to that countdown.
"The way that sterling reacted last week to rumors that you're going to see an extension (to Article 50), showed that there is a lot priced in to the market already."
An extension would have to be approved by the EU's other 27 members. It's unclear in what circumstances they would approve that and by how long they would agree to extend it.