Why are MPs going to vote on just the Brexit withdrawal agreement?

MPs will be voting again on Friday. Photograph: Dan Kitwood/Getty ImagesWhat is the withdrawal agreement? This is the agreement that covers the £39bn payment from the UK to the EU, citizens’ rights of non-Brits in the UK and British citizens in other EU countries and the backstop on the border between Northern Ireland and the Republic of Ireland. This is a legally-binding document and has to be passed by the British and the European parliaments before the UK can leave the European Un