Judges at Scotland's highest civil court will not rule on a legal bid aimed at forcing Prime Minister Boris Johnson to send a letter requesting a Brexit extension if no withdrawal deal is reached by October 19 until after that date.

The requirement for the prime minister to request a Brexit extension if no withdrawal deal is secured with the EU by 19 October is a key provision of the so-called Benn Act, passed by MPs in a bid to prevent a no-deal departure.

Campaigners had lodged an appeal at the Court of Session in Edinburgh after the dismissal of a legal action aimed at forcing Mr Johnson to request a Brexit extension if there is no deal by that date.

They also asked the Court of Session to use the unique power of "nobile officium" which would allow an official to send a letter on behalf of Mr Johnson if he refuses.

However three senior judges said they would not make a ruling until 22 October, after the deadline.