Lady Hale, Deputy President of the UK Supreme Court, will not stand aside from the full court hearing of the appeal over the article 50 notice to quit the European Union, despite a row over whether an address she gave earlier this month indicated bias against the Government.

In a lecture entitled "The Supreme Court: Guardian of the Constitution?", given to lawyers and law students in Malaysia, Lady Hale said the case, which concerns whether the Government requires parliamentary approval to give the formal notice, raised "difficult and delicate issues" about the relationship betwen the executive and Parliament. A further question was whether simple authorisation was enough, or there required to be a full replacement of the European Communities Act 1972.

What Lady Hale said was: "The argument is that the European Communities Act 1972 grants rights to individuals and others which will automatically be lost if the Treaties cease to apply. Such a result, it is said, can only be achieved by an Act of Parliament. 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 for the 1972 Act.

"The contrary argument is that the conduct of foreign affairs, including the making and unmaking of treaties with foreign powers, lies within the prerogative powers of the Crown (what you would call the executive power of the Federation). The EU Referendum Act 2015 neither expressly nor by implication required that further parliamentary authority be given to begin the process of withdrawal. 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.

"Just before I left to come here, a unanimous Divisional Court held that the Secretary of State does not have power under the royal prerogative to give notice to withdraw from the European Union. The court held that just as making a treaty does not change the law of the land, unmaking it cannot do so, but triggering article 50 will automatically have that effect. What has to be done instead is perhaps not so clear. But the case is destined for our court, so I must say no more."

Campaigners to leave the EU however accused her of indicating views on the case ahead of the appeal, and suggesting fuller legislation as a delaying tactic. Former Justice Minister Dominic Raab commented: "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. If judges dip their toes in political waters, by making speeches outside the courtroom, they are asking to get splashed back."

In response the Supreme Court issued a statement that: "Lady Hale was simply presenting the arguments from both sides of the article 50 appeal in an impartial way for an audience of law students, as part of a wider lecture on constitutional law. It is entirely proper for serving judges to set out the arguments in high profile cases to help public understanding of the legal issues, as long as it is done in an evenhanded way.

"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."

Although some lawyers have questioned the wisdom of her remarks, Lady Hale has sincer told the Solicitors Journal that she would "absolutely not" recuse herself, adding: "I have exhibited no bias and those that suggested that I have are simply mistaken."

The appeal will be heard by all 11 Supreme Court Justices in the week beginning 5 December.

Click here to view the the text of Lady Hale's speech.