One of Russia’s leading art galleries said it would try to stop the sale of alcohol on its premises after a man attacked a masterpiece with a metal pole after drinking vodka.

The incident at Moscow’s State Tretyakov gallery on Friday caused serious damage to one of the country’s most famous paintings, which depicts Ivan the Terrible cradling his dying son in 1581, and raised awkward questions about how Russia protects its historical and cultural artefacts.

The damaged painting was completed by the renowned Russian realist Ilya Repin in 1885 and was described by its curators on Monday as a masterpiece in the same league as the Mona Lisa.

In an interior ministry video, Igor Podporin, 37, described how he had drunk 100 grams of vodka (approximately 100ml) in the gallery’s cafe, became “overwhelmed”, and then used a metal security pole to strike the canvas several times.

Zelfira Tregulova, the Tretyakov’s director, said she wanted to stop the sale of alcohol on the gallery’s premises and would hold talks with the lessees of an on-site cafe and restaurant.

“As we’ve now understood, there were small bottles of wine or cognac in the cafe. We’re going to talk to the cafe and ask them to remove them,” she told a news conference.

It would be harder to persuade a separate restaurant, accessible from both the gallery and the street, to stop selling alcohol, she said.

“The incident was awful and frightening and speaks to the aggression which reigns in society,” said Tregulova, who said she believed people were increasingly unable to distinguish between works of art and the documentation of historical facts.

A screen shows the blows inflicted on the painting. Photograph: Sergei Fadeichev/Tass

Vladimir Aristarkhov, the deputy culture minister, said jail time for such attacks should be sharply increased from the three-year maximum. He added that Russia’s museums had a shortfall of about 1,000 security guards, and called for the attacker to be made an example of.

The Tretyakov’s curator, Tatyana Gorodkova, said Podporin shouted something at the time of his attack to the effect that Ivan the Terrible did not kill his son. The painting depicts the tsar cradling his son after dealing him a mortal blow.

Some Russian historians and nationalists dispute the idea that Ivan murdered his son.

The painting, which will be protected by a bulletproof case after being restored, has never been valued because it has never been loaned, but another work by Repin sold for over $7m in 2011.

When asked if she took responsibility for the attack, Tregulova said the incident had been hard to stop. “It was not possible to do anything. It was a question of seconds,” she said, adding the gallery planned to review its security.