Lawyers have been gearing themselves up in the wake of the EU referendum to ensure any eventual UK withdrawal is achieved lawfully.

A group of unnamed businesses and individuals have instructed London law firm Mishcon de Reya to ensure the UK government does not invoke Art 50 of the Treaty of European Union, the procedure for withdrawal from the EU, without an Act of Parliament.

The firm has instructed public law specialists Lord Pannick QC and Tom Hickman of Blackstone Chambers, along with EU law experts Rhodri Thompson QC of Matrix Chambers and Anneli Howard of Monckton Chambers.

Expert opinion is divided over whether parliament’s approval is needed or whether the deed can be done by the Prime Minister under prerogative powers.

The High Court has already been asked by a UK citizen, Deir Dos Santos, to grant permission for a judicial review seeking a declaration that only parliament can authorise EU withdrawal. Dos Santos has instructed Dominic Chambers QC of Maitland Chambers.

In addition, tax barrister Jolyon Maughan QC has crowdfunded more than £10,000 to instruct a legal team to seek clarification on whether the government intends to trigger Art 50 without a parliamentary vote, and around 1,000 barristers and judges have signed a letter calling for a free vote in the House of Commons on whether Art 50 should be set in motion.

Meanwhile, the Bar Council has said it is ‘ready to assist in achieving an orderly restructuring of the UK’s relationship with the EU’ and will continue to work closely with partners in European Bar Associations. A working group, chaired by Hugh Mercer QC, will explore the implications for the Bar. Chairman, Chantal-Aimée Doerries QC, said: ‘Despite all the turbulence, I am confident that London will remain a leading centre for international dispute resolution.’