(Bloomberg) -- The U.K. believes the Kremlin was behind a hoax call to Foreign Secretary Boris Johnson in which Russian pranksters pretended to be Armenian Prime Minister Nikol Pashinyan.

The phone conversation, on May 8, failed to deliver the gaffes or indiscretions that the callers were hoping for, but British officials say it has the hallmarks of an attempt by President Vladimir Putin’s government to discredit Britain in the wake of the poisoning of former spy Sergei Skripal and his daughter Yulia.

Two U.K. officials, speaking on condition of anonymity, said the Kremlin was trying to save face after the Skripal affair. Johnson’s deputy, Alan Duncan, originally took a call from the pranksters before they were passed on to the foreign secretary.

“If this was an attempt to ridicule us, it has totally backfired,” Duncan told Bloomberg News on Thursday. “All it has done is make the Russians look even sillier than we knew they were.”

The Foreign Office in London said in an emailed statement that Johnson realized “it was a hoax, and ended the call.” It added: “The use of chemical weapons in Salisbury and Syria, and recent events in Armenia are serious matters. These childish actions show the lack of seriousness of the caller and those behind him.”

No Fool

Details of the call were published in the pro-Kremlin tabloid newspaper Komsomolskaya Pravda and those responsible expressed disappointment that Johnson had not made a fool of himself.

Johnson turned out to be “a smart diplomat, an intellectual,” Alexei Stolyarov, told the newspaper. It’s “probably the first time the person we talked to who was not a fool,” he said.

During the 18-minute call on May 8, Johnson repeated his public assertions that Britain doesn’t want a new cold war, and is “absolutely sure” that Russia was behind the poisoning of the Skripals in England in March. “Almost 100 percent,” he said.

“Russians should know that the U.K. will counter them firmly and we will continue pressing on some of Putin’s circle oligarchs,” Johnson said, according to a transcript published by the newspaper. “We will look for ways to put more pressure on them in line with our legislation.”

The transcript appears to confirm the Foreign Office line that Johnson realized he was being tricked and extracted himself from the conversation.

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--With assistance from Stepan Kravchenko.

To contact the reporters on this story: Tim Ross in Santiago, Chile at tross54@bloomberg.net;Thomas Penny in London at tpenny@bloomberg.net

To contact the editors responsible for this story: Flavia Krause-Jackson at fjackson@bloomberg.net, Stuart Biggs

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