Youth Demand supporters have pasted a photo of a mother and child in the Gaza strip over a Picasso masterpiece at the National Gallery.
The two protestors walked into room 43 of the gallery just before midday and plastered the photograph over the protective glass of the Motherhood painting.
The pair then poured red paint onto the gallery floor before police were called and arrested them.
The image, which shows a Gazan mother clutching onto her injured child whilst covered in debris, was taken by Palestinian journalist Ali Jadallah.
The action group, which stemmed from the student branch of Just Stop Oil, says it is calling for a two-way arms embargo on Israel and for the new UK government to halt all new oil and gas licences granted since 2021
A National Gallery spokesperson said no damage had been caused to any of the paintings in the room, but confirmed it was currently closed to the public following the incident.
It is the latest in a long line of stunts which have been carried out by protestors at the gallery – Just Stop Oil activists have thrown soup on two of Vincent Van Gogh’s paintings on two separate occasions.
One of the activists involved in the stunt was 23-year-old Jai Halai, an NHS worker from London.
He said: ‘I’m taking action with Youth Demand because at this point it’s been over one year of seeing my colleagues in the healthcare field decimated. Decimated by bombs, by bullets and by having to operate, with no medical equipment, on starved children.
‘We need a two way arms embargo on Israel now; 87% of the British public want this and never before have they been more disillusioned with our Government and political class who do not represent us. We need a revolution in our democracy.
‘Direct action is what gave us our rights and is the only way to move us towards proper justice. Civil resistance is our duty as young people: to defend those without a voice today and to defend our futures. It’s time to take to the streets; bring on the revolution.’
The targeted artwork was painted by the famous Spanish artist in 1901 and depicts a mother cradling a naked child, its long limbs folded into her embrace as if still in the womb.
Also taking part was Politics and International Relations student Monday-Malachi Rosenfeld, 21, who said: ‘I’m taking action because as a Jew, I feel like it’s my duty to call out the genocide being committed in Gaza.
‘I want the world to know this isn’t in the Jewish name and I want to see a free Palestine. When Keir Starmer says Britain stands with Israel he’s wrong.
‘We know very well that this is a genocide, not ‘self defense’ and we as the people of Britain say enough is enough.’
Last month, two of the group’s activists spray painted the words ‘Genocide Conference’ on the front entrance of the Labour Party conference.
The protestors spray painted the words across 12 windows before security noticed at the Liverpool conference. They were then tackled by plain clothes police officers and arrested.
The group’s latest stunt comes a month after supporters from their sister organisation Just Stop Oil supporters threw soup over two of Vincent van Gogh’s paintings.
Their actions came on the same day that fellow activists Phoebe Plummer 23, and Anna Holland, 22, were jailed for doing the same thing to the famous painter’s Sunflowers masterpiece.
After they covered the paintings in soup, the three activists took off their jackets to reveal Just Stop Oil t-shirts and one said: ‘Future generations will regard these prisoners of conscience to be on the right side of history.’
Just Stop Oil later revealed the three activists as community worker Phil Green, 24, from Cornwall, retired professor Ludi Simpson, 71, from Bradford and grandmother Mary Patricia Somerville, 77, from Bradford.
The National Gallery confirmed the three activists had been arrested and the paintings remain unharmed.
Plummer and Holland were jailed for two years and 20 months respectively after causing as much as £10,000 worth of damage to the artwork’s gold-coloured frame when they targeted it at London’s National Gallery just under two years ago.
Staff at the gallery inspected the painting, worth up to £72.5m, and frame for damage while the women were still attached to the wall, and were worried the soup may have dripped through the protective glass.
The pair had been to the museum in Trafalgar Square a day before the incident and bought the tins of soup from a Tesco supermarket in central London.
They denied but were convicted of damaging property by a jury after a four day trial at Southwark Crown Court.
Plummer said she had ‘made peace’ with her decision and smiled as she was handed her sentence.