A report into possible Russian interference cannot rule out the possibility that the Kremlin impacted the 2016 Brexit vote.

The UK Intelligence and Security Committee said Russia could have influenced the British decision to leave the European Union, according to The Times newspaper.

Boris Johnson is under growing pressure to publish the report.

It also raises questions about links between himself and the Conservative party to Russian donors.

However, the UK government is not set to publish it until after the December 12 general election.

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A report into possible Russian interference that Boris Johnson's government is refusing to publish reportedly said that the Kremlin may have affected the 2016 Brexit referendum.

The Times newspaper reports that the UK Parliament's Intelligence and Security Committee was not able to rule out the possibility that Russia influenced the British vote to leave the European Union.

The committee concluded that any Russian interference in the 2016 vote was ultimately "unquantifiable."

The report criticised British intelligence services for not devoting enough resources to combating the threat of Vladimir Putin's Russian regime to the UK, the Times adds. The committee studied possible Russian interference in British democracy for 18 months.

Prime Minister Boris Johnson is under growing pressure to publish the report.

The UK Parliament's Intelligence and Security Committee, chaired by Dominic Grieve, gave Johnson its report weeks ago. However, the UK government is not set to publish it until after the December 12 general election.

Last week, former US presidential candidate, Hilary Clinton, said it was "inexplicable and shameful" that the UK government had not already released its findings.

She told the BBC she was "dumbfounded" by the decision and added: "Every person who votes in this country deserves to see that report before your election happens.

"Because there is no doubt — we know it in our country, we have seen it in Europe, we have seen it here — that Russia, in particular, is determined to try to shape the politics of western democracies.

"Not to our benefit, but to theirs."

The report also reportedly raises questions about links between Johnson, his Conservative party, and Russian donors.

Nine recent Russian donors to the Tory party were named in the report, it emerged last weekend.

The report identified close links between these donors to the Conservative party and the Russian government.

Among those donors named in the suppressed report were Alexander Temerko, who worked for the Russian defence ministry and has previously boasted that the prime minister is his "friend."

Temerko donated more than £1.2m to the Conservatives over the past seven years.

Other Russian donors to the Conservative party include Lubov Chernukhin, who is married to Vladimir Chernukhin, a former ally of Putin.

Chernukhin previously paid £160,000 for a tennis match with Johnson and former prime minister David Cameron and has donated more than £450,000 in the past year.

A recent investigation by Open Democracy found that the Conservative Party received at least £498,850, or about $642,000, from Russian business executives and their associates between November 2018 and last month.

This was a significant increase from the previous year when such donations amounted to less than £350,000.

The increase came despite increased pressure on the party to cut its ties to Russian oligarchs since the poisoning of Sergei and Yulia Skripal in Salisbury last year.