LONDON - Anti-Brexit campaigners claimed victory after Scotland's highest court decided on Wednesday to wait before ruling whether to force British Prime Minister Boris Johnson to seek a Brexit delay if he has not struck a deal in 10 days.

The campaigners had sought an order from the court asking it to order Johnson to abide by a law that requires him to ask for a Brexit extension if he has failed to secure a deal by Oct. 19 and to send the letter to the European Union if he refused to do so himself.

Government lawyers told Edinburgh's Court of Session that Johnson accepted that he must carry out the requirements of the law, known as the Benn Act, even though he has publicly said he would rather be "dead in a ditch" than ask for any further delay.

The court decided it would delay consideration of the case until Oct. 21, after Johnson will have had to ask for an extension if the event no deal has been agreed.

"We have extracted from him a promise that he will comply with the law," said Jo Maugham, a tax lawyer who was one of those behind the Scottish case.

"If he breaks that promise he will face the music - including possible contempt proceedings."

(Reporting by Michael Holden; editing by Guy Faulconbridge) ((michael.holden@thomsonreuters.com; +44 207 542 3213; Reuters Messaging: michael.holden.thomsonreuters.com@reuters.net))