Russia and the UK are at odds amid reports Moscow attempted to influence the Scottish independence vote and tried to steal details of research into coronavirus vaccines.
Sometimes dubbed the “Russia report”, after months of delays it is being published on Tuesday by the Intelligence and Security Committee.
It is based on secret material from Britain’s intelligence agencies and is expected to outline the threat Russia poses to the UK as well as efforts to counter it.
The Daily Telegraph has reported the probe found “credible open-source commentary that Russia undertook to influence the campaign on Scottish independence” in 2014.
But the paper added the 18-month investigation did not find Moscow played any part in the 2016 Brexit vote.
Foreign Secretary Dominic Raab has claimed it was “almost certain” Russia tried to interfere in the 2019 general election.
Mr Raab said last week that “Russian actors” had tried to influence the 2019 contest by “amplifying” stolen Government papers online.
The documents, relating to US-UK trade talks, were picked up by then Labour leader Jeremy Corbyn to back his claims the Conservatives were preparing to “sell off” the NHS.
The Russian Embassy in London said the nation “has not and will never interfere in the internal affairs of the United Kingdom, especially in the context of democratic elections”.
Britain, the US and Canada have claimed Russian intelligence-linked hackers tried to steal details of research into coronavirus vaccines.
It was alleged a group of hackers, known as the Dukes or Cozy Bear, had targeted research bodies around the world – including in the UK.
Security Minister James Brokenshire said the National Cyber Security Centre was 95% certain cyber attacks against labs developing a Covid-19 vaccine were carried out by the Russian state.
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