Former justice minister David Ford is among a cross-community group of politicians and human rights activists whose lawyers wrote to Prime Minister Theresa May and other cabinet ministers.
They claim that a number of criteria must be met before the Government can trigger Article 50 of the Treaty on European Union, including that parliamentary legislation authorising it and the consent of the Northern Ireland Assembly are required.
But according to their legal representatives, the ‘various assurances sought by our clients have not been forthcoming and, indeed, the response heightened their concerns about the approach the Government was likely to take.
‘In light of this, Papers were lodged in the High Court in Belfast on Friday seeking leave to apply for judicial review.’
Belfast law firm Jones Cassidy Brett, which is representing Mr Ford among other political figures, said in a statement that it received an inadequate response from the Secretary of State for Exiting the European Union, David Davis, and Northern Ireland Secretary James Brokenshire.
‘This claim differs from other actions being taken in relation to the triggering of Article 50,’ the firm said in the statement. ‘The actions in London do not, it is understood, deal with the unique requirements of Northern Ireland constitutional law and statute.’
Fiona Cassidy of Jones Cassidy Brett said the issue is likely to come before the courts this autumn.