The Last Night of the Proms is known for its patriotic flag-waving as the show draws to a close, with hundreds of Union Jacks on show.
This year attendees carried on the tradition of also waving European Union flags, leaving Brexiters very unhappy.
The EU Flag Mafia said that it handed out 10,000 EU flags outside the Proms “in support of Gigging British Musicians in trouble due to a failed Brexit”.
There were protests by musicians outside of the venue at the post-Brexit changes that make gigging across Europe so much harder and more expensive than before.
But not everyone got behind the campaign.
One social media user tweeted: “Go away with your EU flags and hats.
“Would it kill you to celebrate with the Union Jack for one night? Be patriotic, this is the Last Night of the Proms.”
Another added: “I really do wonder about some folks.
“Last Night of the proms, Rule Britannia, Land of Hope & Glory.
“There they are EU Berets atop their bobbling heads, waving their little flags – I mean has anyone told them we are out of the EU and it’s all over.”
A third wrote: “Last night of the Proms.
“Why are idiots wearing EU hats, waving EU flags, but singing Rule Britannia? What hypocrites.”
A fourth said: “Idiot of the week awards goes to all those Remainers with EU flags and hats at the last night of the Proms.
“Five years on and still can’t accept the result of the referendum.”
But there was also a groundswell of support for the gesture to the EU.
Wolfgang Blau tweeted: “London, last night, Royal Albert Hall. The European Dream can be maligned, ridiculed, sabotaged. It will still outlast us all.”
The European Movement UK tweeted: “Poor, poor Express, so offended by people proudly displaying their identity and standing up for touring musicians, whose livelihoods have been severely impacted by dire Brexit bureaucracy.”
Graham Simpson simply wrote: “Glorious”
Paul Hampton” tweeted: “WOW – lots of EU flags at BBC Last Night of the Proms”
Dr Mike Galsworthy tweeted: “Given that Brexit has so thoroughly screwed the music industry… …it’s lovely to see this new tradition of European & UK flags together at the Proms really take hold.”
Guy Verhofstadt tweeted: “Lovely indeed to see so many European flags during the night of the Proms…”
“Musicians protesting about losing their FOM at the Proms,” wrote EU Flag Mafia.
Related: M&S could bid adieu to France as post-Brexit customs rules bite