Can Spain really veto the withdrawal bill?
No, and the agreement has now been approved by the European council (on which the leaders of all EU countries have a seat) anyway. Individual EU states couldn't veto the withdrawal agreement on their own at the European council—it only required 20 of 27 members to vote in favour.
However, Spain will have a potential veto much later in the Brexit process (as will every other EU country).
The withdrawal agreement sets up a transition period between the UK and the EU that’s meant to last until the end of 2020 (although it could be extended by a year or two) while both sides try and negotiate a final trade deal. This final trade deal will set out the terms of the UK and EU’s future relationship.
The Institute for Government told us that Spain—like any other EU member country–can veto that final agreement. That’s because this needs the unanimous approval of all 27 EU members at the European council (as well as the approval of the European parliament and some national and regional parliaments).
This article is part of our Ask Full Fact series on Brexit, answering your questions about Brexit and the latest negotiations between the UK and the EU.