Britain blamed Russia on Monday for calls to Defence Secretary Ben Wallace and Home Secretary Priti Patel by an impostor posing as the Ukrainian Prime Minister.
The Prime Minister’s official spokesman said: “The Russian state was responsible for the hoax telephone calls made to UK ministers last week.
“This is standard practice for Russian information operations.”
He added: “Disinformation is a tactic straight from the Kremlin playbook to try to distract from their illegal activities in Ukraine and human rights abuses being committed there.
“We are seeing a string of distraction stories, and outright lies from the Kremlin, reflecting Putin’s desperation as he seeks to hide the scale of the conflict and Russia’s failing on the battle field.”
An unsuccessful attempt was also made to target Culture Secretary Nadine Dorries with the operation.
Armed forces minister James Heappey has insisted that Mr Wallace did not say anything inappropriate given his security training, and Ms Patel is also said to have not divulged any sensitive information.
However, Whitehall officials are braced for clips of the hoax calls to be put out by the Kremlin, which could also be doctored as part of moves to split the West’s response to the crisis which has seen unprecedented sanctions imposed on Russisa.
They are urging broadcasters not to amplify Russian disinformation being put out to undermine the sanctions and other measures being taken by the US, Britain and allies following the “barbaric” invasion of Ukraine which has left thousands of civilians dead.
A cross-Whitehall inquiry has been launched into how the Russians allegedly managed to set up calls with two Cabinet ministers – in itself deeply embarrassing even if nothing inappropriate was said.
Mr Wallace is reported to have become suspicious about the audio/visual call, which was set up through another department, when the Ukrainian “Prime Minister” started asking about troop movements.
The Defence Secretary tweeted on Thursday: “Today an attempt was made by an imposter claiming to be Ukrainian PM to speak with me. He posed several misleading questions and after becoming suspicious I terminated the call.
“No amount of Russian disinformation, distortion and dirty tricks can distract from Russia’s human rights abuses and illegal invasion of Ukriane. A desperate attempt.”
The call to Mr Wallace, which lasted around ten minutes, is said to have been made through a faked embassy account, with a “lookalike Prime Minister”, and a formal office background.
He is said to have been asked about the peace talks and Nato.
Home Secretary Priti Patel also revealed last week that she had been targeted.
“This also happened to me earlier this week,” she said.
“Pathetic attempt at such difficult times to divide us. We stand with Ukraine.”
Russia and other hostile states are said to be launching almost daily cyber and disinformation attacks on Britain, with the vast majority being stopped.