British graffiti artist, Banksy made a surprise appearance at the Venice Biennale, protesting against the city’s problem with cruise ships.

The artist, who has never been identified, and is known for his controversial street art, uploaded a video to Instagram of himself setting up a stall near St Mark’s Square.

The paintings, titled ‘Venice in Oil’, is displayed in a number of gold frame paintings that show fragments of a cruise ship.

The sort clip shows Banksy himself, setting up the stall with passersby (and a stray cat) studying the artworks. Later, Venetian police speak to Banksy, telling him he has to move on as the famous artist had no permit. “You have to have authorization or you have to go away. You can’t stay here,” says the policeman.

The video then cuts to a massive Costa Cruises ship sailing away past a row of gondolas. The video, which was uploaded to Instagram nine hours ago, is captioned, “Setting out my stall at the Venice Biennale. Despite being the largest and most prestigious art event in the world, for some reason I’ve never been invited.”

The locals of Venice have been in uproar with the number and size of ships sailing into the sinking city. Banky’s work appears to be referencing the pollution that ships cause to the city as they cross the Grand Canal.

The city’s booming tourism has threatened its survival, and in 2016, Venice’s No Grandi Navi (“No Big Ships”) protest was one of the most dramatic scenes seen. Locals took the Giudecca Canal in small fishing boats to block the passage of six large cruise ships.

While plans were announced to reroute the largest ships to a new dock in Marghera (still to be built), campaigners are still arguing for a dock outside the lagoon at the Lido where heavy cargo ships unload.