Rude gestures are rarely found on stamps, but Ukraine’s most famous stamp features one. It shows a soldier giving a middle finger to a Russian warship, referring to a standoff on Snake Island on the first day of a full-scale invasion nearly three years ago.

The Russians demanded surrender, but the Ukrainians refused in unprintable language.

The warship in question, the cruiser Moskva, was sunk by the Ukrainians two days after the stamp was released, and it sold out within a week of its release.

That’s what stamps are for, everything that’s left behind is to government delegation Represent Ukraine on the world stage.

Ihor Smilyansky, the head of the Ukrainian postal company Ukrposhta, admitted that this was an offensive move.

“It was my decision. I said – I don’t care what other people think. I just believe it’s the right thing to do,” he told the BBC. “I know it goes against all the philatelic (stamp research) rules and all the rules. But we’re just going to break the rules.”

Ukrposhta often tests its designs among the public, and the results of such online polls tend to be highly political.

Thus was born Ukraine’s best-selling stamp, which features a Ukrainian tractor pulling a captured Russian tank and features the popular wartime greeting: “Good evening, we are from Ukraine.”

Ukrposhta has sold about 8 million of these stamps.

Ukraine themed stamps Famous Patron of Mine-Sniffing Dogs Ukrposhta made around $500,000 (£400,000): 80% of the money was spent on mine-clearing equipment and the rest went to animal shelters.

another stamp Murals left by famous graffiti artist Banksy On the outskirts of Kiev, 10 air raid shelters were financed on a building destroyed by shelling. The stamp features another popular but unprintable Ukrainian slogan – this time directed at Vladimir Putin.

Ihor Smyansky said that some elements of humor were added to the stamps of the Ukrainian Postal Service to maintain Ukraine’s morale during the war with Russia.

“Humor has become the fighting strength of Ukrainians in this war,” he told the BBC. “Even in the most difficult situations, you have to keep a sense of humor. That’s sometimes what our stamps are about.”

Oscar Young of British stamp dealer and auctioneer Stanley Gibbons said it was unusual for Ukraine to focus its stamps on the war.

He told the BBC: “Generally speaking, stamps are artistic and polite, but there’s something very crude, rude, vulgar in a stamp that’s very unique to these particular issues.”

He said the candid image used on the warship stamp made the stamp so famous and caused such a stir when it was issued.

The unique character of Ukrainian stamps has won them the favor of collectors around the world.

Laura Bullivant from Gloucester, England, thinks other stamps look bland in comparison.

“I think they’re like the Ukrainian thought process, they’re strong and they’re not going to give in to anything that comes into their country,” she said.

“In a time of great concern and horror, they have brought something to the game that no other country has been able to do.”