A law firm have taken steps to ensure that the UK government will not trigger an exit from the EU unconstitutionally or unlawfully.
Law firm Mishcon de Reya has been in contact with government lawyers since 27 June to seek assurances that the government will uphold the UK constitution and protect parliamentary sovereignty.
In a statement, the firm said that legally the decision to trigger Article 50 was down to Members of Parliament and not the government.
It added that it would be unlawful for the government to take action without allowing MPs to debate and vote on the subject.
Kasra Nouroozi, partner at Mishcon de Reya, said: "The outcome of the Referendum itself is not legally binding and for the current or future Prime Minister to invoke Article 50 without the approval of Parliament is unlawful.
"We must make sure this is done properly for the benefit of all UK citizens. Article 50 simply cannot be invoked without a full debate and vote in Parliament."
A Cabinet Office spokesperson said: "As the Prime Minister said in the Commons, we have now got to look at all the detailed arrangements, and Parliament will clearly have a role in making sure that we find the best way forward.
"It will be important to ensure in moving ahead that the interests of all parts of the United Kingdom are protected and advanced."