Prime Minister Theresa May holds a regional cabinet meeting in Runcorn, Cheshire, as she launched her industrial strategy for post-Brexit Britain with a promise the Government will "step up" and take an active role in backing business, Britain, January 23, 2017. REUTERS/Stefan Rousseau/Pool

DUBLIN (Reuters) - A legal challenge to determine whether Britain’s exit from the European Union can be reversed once triggered is to be filed in Dublin on Friday with the aim of securing a referral to the EU’s top court within months, a lawyer taking the case said.

British Prime Minister Theresa May says she will invoke Article 50 of the EU’s Lisbon Treaty by the end of March, triggering two years of formal divorce talks.

Lawyers for the British government have said that, once started, the process is irrevocable, but some EU leaders say Britain can change its mind.

London tax lawyer Jolyon Maugham, who is leading the case to determine whether Britain can unilaterally revoke Article 50 without the consent the other 27 EU states, said in a statement that he hoped the case would be heard by the Irish High court by March or April.

In the best-case scenario, the case might then be before the European Court of Justice before the summer, Maugham said.

He said English, Welsh and Northern Irish members of the Green Party will be joining the case as plaintiffs, he said.

Ireland was chosen as the case had to be brought in the EU but outside Britain, and its legal system was similar to Britain’s. The plaintiffs say the Irish government colluded in a breach of the EU Treaties by wrongly excluding Britain from some EU Council meetings after the referendum.