Art galleries on high alert for fresh attacks as Just Stop Oil activists pledge to ramp up protests

Galleries and museums have been warned to be very alert to copycat attacks on artworks as environmentalists secretly pledged to “escalate” their action.

Tourist attractions are thought to have stepped up their security measures after two Just Stop Oil activists threw Heinz tomato soup at Van Gogh’s masterpiece, Sunflowers, at the National Gallery this month. It was protected from permanent damage by a glass screen.

But there was little sign that the National Gallery had stepped up its checks when a Daily Mail reporter paid a visit this week.

An airport-style metal detector sounded no alarm when the reporter entered the building with a bag containing a metal bottle of water.

And security personnel looked no further than the top layer of the bag, which could have easily hidden a can of tomato soup.

There were staff members in several rooms, including at the entrance to room 43 – home to works by Matisse, Picasso and Van Gogh.

However, the reporter was able to stand within easy reach of Sunflowers – reappearing after a cleanup – and remove the flask from the backpack without being approached.

There was a similarly distant approach to security at the Tate Modern and Victoria and Albert Museum in central London – none of which questioned our reporter’s backpack with any force during visits last week.

Last week senior Just Stop Oil leaders planned to step up their action, saying damaging artworks would be “proportionate.” Pictured: Protesters glue their hands to the frame of Leonardo Da Vinci’s The Last Supper on July 5

The multimillion-pound sunflowers — considered the most popular artwork in the National Gallery — were behind a piece of protective glass screen when it was hit.

Just Stop Oil leaders plan to stage protests, saying damaging artworks would be “proportionate.”

One insisted, “Actions are escalated. Material damage is going to happen.’

Art experts said today that a balance had to be struck between public enjoyment and safety, but the publicity surrounding the Sunflowers stunt will have upset gallery leaders.

David Dallas, chief executive of Doerr Dallas Valuations in Surrey, said: “The National Gallery is aware of insane copycat protests.

“But the reality is you just can’t budget them. You can’t really protect everything from every eventuality.

“Most people have good intentions, so security is often not very thorough, because then the queues to get in would be huge and there would be endless complaints.

‘You have to weigh the accessibility against the security of the photos, and that is not easy.

“You just can’t budget for the idiots.”

Art historian Richard Morris said the extra vigilance needed to guard against protests would likely cost galleries crucial funds.

He said: ‘Of course art galleries and museums of any size will be on the alert in case someone randomly throws something at a painting or a work of art.

‘Many art galleries are already struggling to stay open due to high energy costs; the extra cost of security will be the final nail in the coffin for many and some will close; people lose their jobs.

“There are no winners in this kind of random action. It will deprive people of the pleasure of viewing and understanding art made to tell important stories and struggles, struggle that continues into the modern age, where this winter some people will come to galleries and museums to keep warm.

“A great irony of these protests is that they were filmed on smartphones manufactured in China, one of the largest consumers of oil in the world. These actions have a cascade. It’s not victimless.’

A spokesman for the National Gallery said: ‘We are constantly monitoring our security arrangements.

“But we don’t talk about our safety publicly, because that in itself would endanger our safety.”

Two protesters will face charges in December for the sunflowers incident.

Just Stop Oil, which has also recently blocked roads in London, says it is using civil resistance and direct action to pressure the government into halting new permits and fossil fuel production.

How treasures are protected

Museums and galleries use a range of methods to protect prized exhibits.

When Just Stop Oil protesters threw tomato soup at Sunflowers — protected by a thin glass screen — the staff reportedly cleaned it with kitchen towels and put it back on display a short time later.

Many museums around the world use a special plastic known as Plexiglas to protect treasures.

The material provides protection from sunlight, reduces reflection and prevents insects from depositing feces that can cause serious damage.

However, some masterpieces have an extra layer of security.

The Mona Lisa is protected by bulletproof glass in the Louvre in Paris, where visitors are blocked from getting close to the painting by a wooden rail barrier.