Was the UK forced to use burgundy passports by the EU? According to Theresa May's Twitter: > The UK passport is an expression of our independence and sovereignty – symbolising our citizenship of a proud, great nation. That's why we have announced that the iconic #bluepassport will return after we leave the European Union in 2019. But did the EU ever force the UK to use burgundy passports in the first place? Are they unable to switch without leaving the Union?

According to the BBC. no. The EU does not impose passport color restrictions on any member states and several states do not in fact have a burgundy passport.

The EU has mandated several wording and content changes to assist in freedom of movement for EU citizens and as this Guardian article (soft paywall) notes, most of the changes to size, biometrics and other security features are EU regulations passed in order to comply with US and ICAO regulations. If UK passport holders want to enjoy ease of travel around the world they'll still have to keep those parts.

Finally a Wikipedia link on Passports of the European Union.