Brexit on a knife edge

The DUP say they won't back Theresa May's Brexit deal.

It's after Britain's Attorney General said changes to it mean it's less likely the UK will be trapped in the Irish backstop, but still wouldn't be able to leave it without the EU's agreement. It would mean different trade rules for Northern Ireland. MPs are due to vote on it tonight. The British Prime Minister says if MPs don't back it there could be no Brexit at all.