EU legislation may have to be replaced wholesale before Brexit, according Deputy President of the Supreme Court, Lady Hale.

The judge said in a speech to law students in Kuala Lumpur that the court could go further than simply requiring legislation permitting article 50 to be triggered.

The court is due to rule on the issue in the wake of the High Court’s judgment confirming that MPs must approve the triggering of article 50.

Lady Hale said: “Another question is whether it would be enough for a simple act of Parliament to authorise the government to give notice, or whether it would have to be a comprehensive replacement of the 1972 act”.

Outlining the government’s likely argument, she said: “The basis on which the referendum was undertaken was that the government would give effect to the result. Beginning the process would not change the law.”

All 11 of the Supreme Court’s judges will hear the case.

Conservative MP Dominic Raab said Lady Hale should not have made any public comments on the case.

He said: “If judges dip their toes in political waters by making speeches outside the courtroom, they are asking to get splashed back.”

“I’m all for democratic debate. But you can’t have it both ways. If such a senior judge muses in public about a pending supreme court judgment, the judiciary can hardly scream blue murder if politicians, the media or public respond,” he added.

Sir Bill Cash, another Conservative MP and chairman of the European Scrutiny Committee, said: “I am astounded that a Justice Of The Supreme Court would venture into this territory before hearing the evidence of the case. It appears completely contrary to the proper relationship between the courts and Parliament for her to suggest what Parliament should do.”

A spokesperson for the court said Lady Hale was presenting the arguments of both sides impartially.

They added: “One of the questions raised in these proceedings is what form of legislation would be necessary for Parliament to be able to lawfully trigger article 50, if the government loses its appeal.

“A number of politicians have raised the same question. Though it was not dealt with explicitly in the High Court judgment, it is not a new issue. In no way was Lady Hale offering a view on what the likely outcome might be.”