Home Secretary James Cleverly has accused a stunt at the Glastonbury Festival reportedly devised by the artist Banksy of “trivialising” small boat crossings in the channel.

A small boat filled with migrant dummies in orange life jackets was hoisted into the crowd gathered to watch the band Idles play on the Other Stage at Worthy Farm on Friday night.

Posting on X, formerly Twitter, Mr Cleverly said: “Small boats crossings are deadly and have cost the lives of too many people.

“Festival-goers cosplaying as migrants, and celebrating the actions of people smugglers, while they party is awful.

“Whatever your political views, this isn’t something we should trivialise.”

The boat appeared while the Bristol rock band were performing Danny Nedelko, a 2018 release which begins with the lyrics: “My blood brother is an immigrant, a beautiful immigrant.”

According to The Guardian, the band said the demonstration was devised by Bristol artist Banksy and they were not aware it had happened until after the set had finished.

The Glastonbury Live account also posted an image on Saturday of the artwork returning for Little Simz’ Pyramid Stage slot.

Deputy prime minister Oliver Dowden also hit out at the stunt, telling Times Radio: “I was really saddened by it, actually.

“If you look at what happens with men, women, children being shoved onto those dinghies – the criminal gangs only fill them half with petrol, so they run out halfway across the English Channel and start to sink, endangering people’s lives.

“I don’t think this is a sort of thing to joke around with at Glastonbury.”