A senior European figure has dismissed Theresa May’s claims that the new blue passport is an expression of post-Brexit “independence and sovereignty”, as Britain could have chosen to switch colour while remaining in the EU.

The European Parliament’s chief Brexit coordinator Guy Verhofstadt said there was no EU law “dictating passport colour” so Britain could have brought back the traditional blue travel document at any time.

The Government announced on Friday that burgundy British passports would be replaced with blue and gold documents from 2019 as the contract is up for its regular five-year renewal.

Ms May tweeted: “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 blue passport will return after we leave the European Union in 2019.”

Eurosceptic MPs seized on the news as a symbol of Britain casting off Europe’s influence but Mr Verhofstadt pointed out that Britain could have chosen to switch the colour regardless of Brexit.

There is no Brussels regulation which states that EU countries’ passports have to be a certain colour, only a legally non-binding European Council resolution from 1981 that recommends burgundy.

Mr Verhofstadt tweeted: “There is no EU legislation dictating passport colour. The UK could have had any passport colour it wanted and stay in the EU.”

It comes amid reports that the new passports could spell travel delays and extra paperwork for British citizens unless the Government makes concessions in the Brexit talks.

EU officials told The Guardian that “depending on how negotiations go on all free movement issues after Brexit”, British passport holders could lose the right to use fast-track citizens lanes abroad and might have to use a new visa waiver scheme similar to the American Esta scheme.

Brexiteer MPs are now demanding that the new passports are made in the UK as EU tendering rules mean the documents could be produced abroad.

Prominent Tory backbencher Jacob Rees-Mogg tweeted: “Symbolism is important and I hope it will be printed in the UK too.”

And Conservative MP Andrew Bridgen said: “Passports are symbolic of our national identity and sovereignty and of course they should be manufactured in the UK.”

Brexit: the deciders Show all 8 1 /8 Brexit: the deciders Brexit: the deciders European Union's chief Brexit negotiator, Michel Barnier Getty Brexit: the deciders French President Emmanuel Macron Getty Brexit: the deciders German Chancellor Angela Merkel Reuters Brexit: the deciders Commission President Jean-Claude Juncker EPA Brexit: the deciders The European Parliament's chief Brexit negotiator Guy Verhofstadt Getty Brexit: the deciders Britain's Prime Minister Theresa May Getty Images Brexit: the deciders Britain's Chancellor of the Exchequer, Philip Hammond PA Brexit: the deciders After the first and second appointed Brexit secretaries resigned (David Davis and Dominic Raab respectively), Stephen Barclay is currently heading up the position PA

The new passports will be phased in after the UK leaves the European Union in March 2019, with the EU insignia removed.