Transcript for Brexit deal defeat

A huge defeat for brexit and the British prime minister. Theresa may suffering a crushing blow in parliament today. She may now face a no confidence vote tomorrow. Can she survive? Here's ABC's Terry Moran now. Reporter: A moment of truth for the United Kingdom. Protesters outside parliament. Inside, a fierce debate on prime minister Theresa may's plan for how Britain will leave the European union, brexit. Mr. Speaker, this is the most significant vote that any of us will ever be part of. Reporter: At issue, the terms of the Breck it is deal. Think of it as the divorce agreement between Britain and Europe. How businesses will trade, how people will travel and so much else. The uk remains bitterly divided. The populist movement that triumphed in the 2016 Breck brexit vote remains strong, so does the bitter opposition. Bloody right wing tories. Reporter: But today Theresa may's major effort went down to a thunderous defeat in parliament. The nos have it. Reporter: May needs a new deal with just 73 days now until the deadline hits and Britain might crash out of the European union with now deal, facing economic chaos. David? All right, Terry Moran, who has covered brexit for some time for us. Terry, thank you.

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