London (AFP) - A long-awaited parliamentary report this week failed to confirm suspicions about Russian interference in British politics, including in the divisive 2016 Brexit referendum.
But it laid out the extent to which wealthy Russians -- some with close ties to President Vladimir Putin -- have become an integral part of the highest ranks of British society.
Anti-corruption campaigners have long alleged that Britain and its financial institutions were being used to launder dirty cash from around the world.
"The United Kingdom is hosting billions of pounds of suspicious wealth from Russia," said Ben Cowdock, an investigator at Transparency International UK.
He told AFP £1 billion ($1.3 billion, 1.1 billion euros) of suspicious Russian funds have been pumped into luxury property in London, leading it to be nicknamed "Londongrad".
Pete Duncan, a Russia specialist at University College London, estimated that "hundreds of billions of pounds" have been reinvested from Moscow since the 1990s.
Parliament's Intelligence and Security Committee (ISC) said the current and previous governments had "actively avoided" digging deeper into the source of the money.
It also hit out at huge donations to political parties, particularly Prime Minister Boris Johnson's Conservatives, and the use of PR and law firms to secure top-level access.
"Russian influence in the UK is the 'new normal'," the ISC said in its report, published on Tuesday.
"There are a lot of Russians with very close links to Putin who are well integrated into the UK business and social scene, and accepted because of their wealth."
The ISC named no names and came to no firm conclusions about alleged Russian interference in the Brexit vote or the Scottish independence referendum two years earlier.
But Cowdock said wealthy Russians were regular guests at political party fundraisers.
London's role in suspicious trading of Russian cash gained public attention in a £10 billion scandal involving Deutsche Bank between 2011 and 2015.
Cowdock noted Britain promised to crack down on laundering in 2016, notably setting up a register of the real owners of luxury homes, which are often bought by shell companies.
"That's something that could be brought in very quickly," he said.
Duncan called for British law enforcement organisations like the National Crime Agency, which investigates serious and organised crime, to get more resources to tackle oligarchs.
Last year, Chris Bryant told the Guardian newspaper the Russian embassy wanted him removed as head of parliament's Russia group in 2009 because he was not pro-Kremlin enough.
The Labour party MP accused the Tories of being reliant on Russian money and of having "wilful amnesia" as they sought to reset relations with Russia.
Former British intelligence agent Christopher Steele, who wrote a dossier on US President Donald Trump's alleged links to Russia, said the Kremlin had "a particular interest in and seeming obsession with the UK".
"The Russian elite has succeeded in establishing a powerful interest group/lobby in Britain through lavish expenditure and investment," he said in evidence to the ISC.
"This itself merits closer attention from an intelligence perspective and tighter regulation/policing than is the case at present."
Claims about Russian links to the Conservatives resurfaced this week, with allegations in The Times that 14 ministers had taken money from Russia-linked figures.
They included a £160,000 donation from Lubov Chernukhin, the wife of a former Putin minister, to play tennis with Johnson and his predecessor David Cameron.
Former party chairman Brandon Lewis said donations were "properly declared" -- and from British citizens. "We do not accept funds from foreign nationals," he said.
Another donor, Alexander Temerko, a former figure in the Russian arms and oil industries who became a Putin critic and gave £1 million to the Tories, said this week he had "zero" political influence.
Cowdock and Duncan said Britain already has a sizeable legislative arsenal to fight money-laundering but it was not being applied.
Real estate agents, law firms, public relations companies and others were often all too prepared to turn a blind eye to the origins of Russian wealth, they added.
But it is their responsibility to verify it.
Duncan pointed out that Russian influence comes despite tense diplomatic ties between London and Moscow since the attempted murder of former double agent Sergei Skripal in Salisbury.
The 2018 attack, using a powerful weapons-grade nerve agent came 12 years after the radiation poisoning death of another former KGB agent, Alexander Litvinenko, in London.
Both caused public outrage, and the latter led to tit-for-tat expulsions of diplomats, despite the Kremlin denying any involvement.