The action, in the area of the Florence Baptistery, was also staged in solidarity with two UG members recently handed nine-month suspended jail terms and 1500-euro fines by a Vatican court.

The sentences and fine were given for a protest in the Vatican Museums last year.

“Today we pour this red liquid over our bodies, a metaphor of the blood of martyrdom, because we choose life in the face of the climate crisis,” UG, which has staged a series of controversial headline-grabbing protests, said in a statement.

The five held up a banner that read “We Won’t Pay for Fossils” (Non Paghiamo Il Fossile), the slogan of an UG campaign calling for an end to public subsidies to fossil fuel projects.

Greenhouse emissions from the use of fossil fuels are the driving force of climate change.

Ester Goffi, 26, and Guido Viero, 61, who, in addition to the suspended sentences, were last month ordered to pay 28,000 euros in damages for gluing themselves to the Laocoon statue last August.

UG said the aim of Monday’s protest was “to bring to the pontiff’s attention the unjust and disproportionate” sentences the pair were handed.

The group said Goffi and Viero have responded to the appeal made by Pope Francis on the need to protect our common home, but had instead “encountered repression”.

Cathedral authorities said the Baptistery was not damaged in the protest.

The red liquid used was a mix of tomato sauce and blueberries.

Florence Mayor Dario Nardella on Monday told Ultima Generazione to stop targeting cultural heritage.

“I think the environmental-emergency battle is one for citizens, institutions and civil society to wage together,” said Nardella, who was hailed as a hero by some after he rugby-tackled an UG activist.

The recipient of the tackle was spraying orange paint over the walls of Palazzo Vecchio, the home of Florence’s town hall, in a protest in March.

“I think attacking cultural heritage, even if only symbolically and, unlike the Palazzo Vecchio case, without causing material damage, gives the wrong message” continued Nardella.

“Nature and culture are sisters.

“Hitting one to protect the other is message that, in my opinion, does not win the support of the public.

“I reiterate my appeal to the Ultima Generazione protestors.

“Stop this form of protest and there will certainly be the conditions to work together and for constructive dialogue.

“But you cannot offend, even symbolically, cultural heritage to highlight the real problem of the climate emergency.”

ANSA