The cell’s crucial audiences are in Russia and Ukraine.

Shortly after the start of the invasion, the unit was responsible for disseminating a video in which Boris Johnson directly addressed the people of Russia, telling them in their own language: “I do not believe this war is in your name.” A version of that video translated into Russian was viewed by more than eight million people, according to the unit’s data. 

While, conventionally, if the Government wished to disseminate a video of the Prime Minister it would rely on posting the clip on official Twitter, Facebook and Instagram pages, here the usual rules do not apply.

For a start, Putin has blocked access to Western social media sites such as Twitter and Facebook in Russia. But there is also an understanding that the Russian president has cultivated an innate hostility towards the UK Government and, as a result, ordinary people are not likely to see nor attach any credence to messages deriving from official Foreign Office and Ministry of Defence accounts.

To get around that problem, The Telegraph understands, the unit has been commissioning advertising agencies to target the Russian population with its messages on sites such as VK, a Russian social media platform. The tactic means that material such as Mr Johnson’s speech will reach the laptops, tablets or mobile phones of people who would never have thought to seek out the view of the British Government.

Heading off  Putin’s lies with ‘pre-bunking’

Members of the unit are also working to expose Putin’s attempts to pre-emptively accuse Ukraine and the West of engaging in activities in which the Kremlin is already involved. Internally this work is known as “pre-bunking”. An example of this was another intervention by Mr Johnson, to warn that Putin may be preparing to deploy chemical weapons in Ukraine, after Moscow claimed it had uncovered a “Ukrainian biological weapons lab”. The US dismissed the claim as “absurd propaganda”.

The information cell is coordinating with embassies abroad to translate and disseminate its “pre-bunking” content around the world, in a bid to overturn the idiom coined by Jonathan Swift that “falsehood flies, and truth comes limping after it”. Officials are now beginning to distribute content in Mandarin, amid questions over China’s potential support of the war.

Currently, the unit is working to expose what it believes are Kremlin preparations to initiate a series of sham referenda to try and carve out new separatist republics from Ukraine, modelled on a similar vote in Crimea in 2014.

“This isn’t a level playing field,” the senior official said. “We know that the Russians won’t hold themselves to the same standards of truth, transparency and accuracy that we in the UK want to uphold. But we see that as part of our armoury in countering the Russian disinformation.

“We know that Russian textbooks dating back to Soviet times, on psyops, psychological operations, taught students that, in defending the state, a lie is not a lie. That’s a weapon. That’s what we’re dealing with and what we’re up against.”