Climate-change activists in Italy threw paint at the entrance of Milan's famed La Scala opera house ahead of the opening performance of the season.

Activists have staged high-profile protests across Europe in recent months, sometimes targeting museums and artworks, calling for tougher action to tackle global warming.

The Ultima Generazione (Last Generation) movement said in a statement they were responsible for the Milan episode.

“Instead of taking the necessary measures to safeguard Italy's future from drought and climate disasters, politics is locking itself away to enjoy a show for a few people,” it said.

Twelve people were killed on the southern Italian holiday island of Ischia last month after a landslide caused by torrential rain devastated a small town.

During the summer, the worst drought in 70 years hit northern areas around the river Po, which accounts for roughly a third of the country's agricultural production

In the past month, Ultima Generazione has hurled soup over a Van Gogh work in Rome, thrown a black liquid on a Gustav Klimt painting in Vienna and flour over a sports car painted by United States pop artist Andy Warhol that was on display in Milan.

Police said they had detained five people following the incident at La Scala, while cleaners swiftly removed the paint from the entrance of the theatre.

La Scala opened its 2022-23 season yesterday, one of the highlights of the Italian cultural calendar, with a performance of the Russian opera Boris Godunov.

La Scala’s choice to open the season with a Russian title has been steeped in controversy in recent months, with many, including Ukraine’s consul in Milan, urging the iconic opera house not to go forward with the performance in order to avert Moscow’s potential use of the news as propaganda.

A group of roughly 30 Ukrainians gathered outside of the theatre during the premiere, protesting La Scala’s choice to highlight Russian culture at a time in which Vladimir Putin is waging a devastating war with roots in the denial of a unique Ukrainian culture. 

Meloni on the red carpet at the La Scala season premiere. (Photo: ANSA)

The protests took place across the main piazza and the group did not enter the theatre, kept far from the dignitaries and political elite in attendance. 

The premiere was attended by Italian Prime Minister Giorgia Meloni and European Commission President Ursula von der Leyen.

"I am intrigued. It's my first time, certainly a good first experience", said Meloni as she arrived at the theatre, walking the red carpet in a navy velvet gown.

Von der Leyen, for her part, told waiting reporters: 

"We must not let Putin destroy this fantastic country (Russia) and so I can't wait to see this work (by Russian composer Modest Mussorgsky)."

− With AAP.