Nicola Sturgeon and Sadiq Khan are leading calls for other parts of the UK to be given special measures on Brexit following reports that Northern Ireland could remain part of the single market and Customs Union.
The leaders, who both represent areas which strongly backed Remain during the 2016 Referendum, said there would be “huge ramifications” if Theresa May allowed the rumoured concessions for Northern Ireland.
First Minister Sturgeon used the news to push her case that Scotland should also be allowed to remain the in the single market post-Brexit, retaining “regulatory alignment with the EU”.
“Right now, Ireland is powerfully demonstrating the importance of being independent when it comes to defending your vital national interests,” she said in a tweet this afternoon.
“If one part of the UK can retain regulator alignment with EU and effectively stay in the single market (which is the right solution for Northern Ireland) there is surely no good practical reason why others can’t,” she added.
Scotland voted strongly in favour of staying in the EU during the 2016 Referendum, 62% to 38%. All 32 of the country’s council areas backed Remain.
News about a potential deal for Northern Ireland has also led to other parts of the UK - including London - to seek exemption from a hard Brexit, with political commentators warning it could have “huge implications for devolution”.
Sadiq Khan, Mayor of London, wrote on social media this afternoon: “Huge ramifications for London if Theresa May has conceded that it’s possible for part of the UK to remain within the single market and customs union after Brexit.
“Londoners overwhelmingly voted to remain in the EU and a similar deal here could protect tens of thousands of jobs.”
Chartered accountant and international political economy professor Richard Murphy added: “The City of London will now be looking at the Northern Ireland EU deal and be asking: ‘Why can they have regulatory alignment but we have to leave the single market?’
“Expect a massive kickback from EC1,” he added.
Almost 60% of Londoners voted to Remain last year - in some boroughs, this figure was as high as 78.5%.
After the Referendum result, more than 180,000 people signed a petition calling for London to become independent and “apply to join the EU”.
Wales has also added its voice to the debate, with its First Minister Carwyn Jones saying parts of the UK cannot “be treated more favourably than others”.
He wrote on Twitter: “If one part of the UK is granted continued participation in the Single Market & Customs Union, then we fully expect to be made the same offer.”
Unlike Scotland and London, Wales actually voted to leave the EU, 52.5% of those who turned out to the polls backing Brexit.
A deal on the Northern Irish border is expected to be agreed today, with Theresa May holding crunch talks in Brussels.
The news has sparked a strong reaction from ardent Brexiteer Nigel Farage, who said politicians have failed millions of Leave voters with Brexit “concessions”.
The Ukip MEP wrote on Twitter: “The UK government’s bitter betrayal of 17.4 million people today is a concession too far, for it will lead to endless problems in Scotland and it damages the integrity of the United Kingdom.”