"As a brewery, we have access to large numbers of bottles, and we also know to handle materials and generally keep everything clean and safe."
Pravda, which also operates a hipster craft beer bar in downtown Lviv, has 25 staff, some of whom learned how to make Molotovs during the protests that toppled Ukraine's pro-Kremlin government in 2014.
Zastavniy said it helped the war effort to have Molotovs that were ready-made by experts, as they could injure the user if not properly constructed. "It can be very dangerous if you don't put a proper cork into the bottle, for example," he said.
At his brewery in an old industrial quarter on the outskirts of Lviv, where start-up firms operate from old shipping containers, Pravda's staff were churning out hundreds of Molotovs on Sunday in the corner of a yard.
They used a mixture of petrol and other household ingredients blended to a specific recipe that they had downloaded from the internet. Ukraine's civil authorities have also issued the public with instructions on how to make Molotovs, urging civilians to use them to "neutralise the occupier".
The Putin Huilo beer - described as a "dry-hopped golden ale" - has a label depicting Putin as a tattooed Russian mafia boss sitting on a throne.
In his lap sits a childlike-version of Dimitry Medvedev, Russia's former prime minister, who holds a toy-like version of the MH17 airliner. The plane was shot down by Russian separatists over Ukraine in 2014, killing 298 civilians.
The label on the bottle, which is printed in English, tells drinkers about the history of Putin's annexation of Crimea. "This action violated world orders established after World War Two, and set off the expansion of Russian terrorism throughout World War Two," it reads.
The beer is brewed in a large champagne-style bottle, which Zastavniy said was the ideal size for petrol bombs. He added, though, that the company would be making Molotovs donated from every brewery in the city. "Even the big brewery from Carlsberg offered their bottles for free," he said.
Asked if the famous Danish brewery had specifically endorsed its brand for use in combat against Putin's forces, Zastavniy was vague.
"They don't specifically say for Molotov cocktails, but you can read it between the lines," he said. "They said: 'if anyone needs thousands of bottles, they can be collected at our address'."
