UKIP set out Brexit vision ahead of triggering of Article 50 Britain's anti-immigration, anti-EU UK Independence Party (UKIP) say they will be the "guard dogs of Brexit" as Prime Minister Theresa May prepares to trigger Article 50 and begin exit negotiations. UKIP leader Paul Nuttall says "Britain must resume full control" when it comes to immigration and "resume its sovereign right to sign trade agreements with other countries". IMAGES AND SOUNDBITES