Britain's Supreme Court has ruled that Theresa May cannot trigger formal exit negotiations with the EU without an act of parliament. The FT's Sebastian Payne talks to Daniel Dombey about how much of a blow the judgement is to Mrs May.<br /><br />► Subscribe to FT.com here: http://on.ft.com/2eZZoLI<br /><br />► Subscribe to the Financial Times on YouTube: http://bit.ly/FTimeSubs<br /><br />For more video content from the Financial Times, visit http://www.FT.com/video<br /><br /><br />Twitter https://twitter.com/ftvideo<br />Facebook https://www.facebook.com/financialtimes
