The Government’s use of the royal prerogative to trigger the process of taking Britain out of the European Union is not being done on a “whim” or “out of a clear blue sky”, the UK’s highest court has heard.

Source:: http://www.belfasttelegraph.co.uk/news/uk/royal-prerogative-is-crucial-in-article-50-appeal-supreme-court-hears-35271262.html