The European Union's highest court is hearing arguments about whether Britain could unilaterally revoke its decision to leave the EU before its planned exit date of March 29 next year

European Union lawyers have rejected a plea by Remain campaigners for parliament to have the power to unilaterally cancel Brexit because it would be a “disaster” encouraging countries to trigger the exit process.

Under the terms of the Lisbon Treaty’s Article 50 exit clause, triggered by the government last year, Britain will leave the EU on March 29, 2019.

Campaigners, including the MPs Chris Leslie and Tom Brake, have taken a case to the European Court of Justice (ECJ) arguing that the government should have the unilateral right to revoke the exit process, giving the House of Commons the power to reverse Brexit.

Hubert Legal, the European Council’s top lawyer, dismissed the idea and warned judges that it would encourage troublesome countries to trigger the