The Kremlin hits out over Roman Abramovich's UK visa
The Kremlin has said that Russian businesses "often encounter unfriendly and unscrupulous actions", after Roman Abramovich's UK visa expired.
The billionaire Chelsea owner is yet to have his UK visa renewed following its expiry in April, a source close to the oligarch has confirmed to Sky News.
An application for it to be renewed has been lodged but the process is taking longer than usual, the source added.
He did not attend Saturday's FA Cup final to see Chelsea beat Manchester United .
It comes amid heightened diplomatic tensions between Russia and the UK in the wake of the Salisbury spy poisoning, along with recent British military involvement in Syria.
The British government would not be drawn on the circumstances surrounding Mr Abramovich's investor visa application, stressing: "We don't discuss individual cases."
Downing Street said visa applications from Russia are handled "rigorously and properly".
"Work is under way in terms of reviewing Tier 1 investor visas," the PM's official spokesman said.
"In 2014-15 we took action to tighten up the Tier 1 investor route, including the introduction of new powers to refuse applications where there are reasonable grounds to believe funds have been obtained unlawfully.
"As a result of these reforms applications reduced by 84%.
"We are currently taking another look at how the route operates and are undertaking further checks on investors who came to the UK through this route before the reforms were introduced."
Mr Abramovich is worth an estimated £9.3bn, according to the Sunday Times Rich List , and has overseen an era of lavish spending at Chelsea since taking charge of the London club in 2003.
He has links to Vladimir Putin's government in Moscow and, earlier this year, was included for the first time on a US list of Russian officials and oligarchs close to the Kremlin that could serve as a basis for future sanctions.
The UK government has toughened its rhetoric against the Kremlin since the nerve agent attack on Sergei and Yulia Skripal in Salisbury in March.
A committee of MPs released a hard-hitting report on Monday, accusing Mr Putin and his allies of "hiding and laundering their corrupt assets in London".
Responding to the report, Moscow accused Britain of unprecedented "anti-Russian mania", warning such an attitude could backfire and scare off foreign investors.
Downing Street has rejected claims it is "turning a blind eye" to "dirty money" from Russia, stressing it is determined to drive "dirty money and the money launderers" out of Britain.
