A recording has surfaced online purporting to be a leaked conversation between two Russian ambassadors discussing which parts of the world they would like to annex after Crimea.

The five-minute recording, laden with expletives, has been posted on YouTube and claims to be a telephone call between Igor Chubarov, Russia's ambassador to Eritrea, and Sergei Bakharev, the ambassador to Zimbabwe and Malawi. It has not been authenticated.

"We've got Crimea, but that's not fucking all folks. In the future we'll damn well take your Catalonia and Venice, and also Scotland and Alaska," says the voice labelled as Chubarov, interspersing his speech with laughter and punning the word for Scotland in Russian so it sounds like "Cattleland".

After this, Chubarov says Russia will make a move for "all those fucking border countries", such as Estonia, as well as Romania and Bulgaria. He adds that the head of the EU mission to Eritrea had jokily said that he wished Russia would "take back" Romania and Bulgaria.

In the end, the ambassadors agree it is probably better to leave Bulgaria, Romania and the "Baltic shit" in the EU for now, and Bakharev says it would be more interesting to go for California or Miami.

"Exactly, Miamiland is fucking 95% Russian citizens," says Chubarov. "We have a full right to hold a referendum." Bakharev suggests holding one in "Londonland" as well, to jovial laughter.

Chubarov congratulates Bakharev on the fact that Zimbabwe was one of only 11 countries, with Syria and North Korea, to back Russia at the UN over its annexation of Crimea. There is also consternation that the "bastards" from Malawi did not support Moscow.

It is possible that the leaking of the recording is revenge for the recent spate of high-profile leaks of western diplomatic discussions over Ukraine. A call between the US assistant secretary of state, Victoria Nuland, and the US ambassador in Kiev was leaked, in which Nuland discussed strategy advice for the leaders of the Ukrainian protest movement, as well as stating "fuck the EU" in reference to differences over Ukraine policy. Nuland as good as confirmed the authenticity of the recording, claiming "the tradecraft is really quite impressive".

Later, a recording of a conversation between the EU foreign policy chief, Lady Ashton, and the Estonian foreign minister, Urmas Paet, was leaked. They discussed the theory that those who died in Kiev violence could have been shot by snipers hired by the opposition rather than government forces, a line which the Russian foreign ministry has pushed.

The reaction in Moscow to the African ambassadors' tape was one more of amusement than anger, especially given that the taped diplomats are significantly lower ranking than Nuland or Ashton.

An official Russian source, claiming Nuland not only swears in English, but is proud of her ability to swear in Russian, said: "If this was their response to Nuland's strong expressions, then be assured that no Russian ambassador could outdo her when it comes to swearing in Russian."

Maria Zakharova, deputy spokeswoman for the Russian foreign ministry, wrote on Facebook that she had no idea who was talking on the tape, but noted that the photograph appended to the YouTube video of Bakharev bore no resemblance to him.

Zakharova insinuated that the recording was clumsy US handiwork and compared it to the incident during the "reset" of relations between Russia and the US, when the then secretary of state. Hillary Clinton. presented the Russian foreign minister, Sergei Lavrov, with a button that was meant to say "reset", but got the Russian word wrong and thus said "overload".

"It's like with the 'overload' button. They wanted to do something better than usual, but it turned out as it always does," wrote Zakharova.

Since the crisis in Ukraine began, there has been an increase in the diplomatic war of words and leaks. Last month, in an official statement detailing what it said were false claims from Russia's president, Vladimir Putin, the US state department said: "The world has not seen such startling Russian fiction since Dostoevsky".

On Thursday, Russia's deputy foreign minister Sergei Ryabkov accused the US of "childish tantrums" over Crimea.

"What can we advise our American colleagues? They should get more fresh air, do yoga, eat healthily, maybe watch some sitcoms on television," said Ryabkov, in comments to Interfax news agency.