LONDON • Chelsea owner Roman Abramovich is unable to travel to the UK at the moment because of delays renewing his visa, according to people familiar with the situation.

The Russian billionaire, who did not watch his team win the FA Cup at Wembley on Saturday, has not been denied a visa, but renewal is taking longer than usual, say sources privy to the matter.

Britain's Home Office, which oversees the country's immigration service, has declined to comment.

Although the reason for the delay is not clear, the tycoon's visa trouble comes at a tense time in UK-Russian relations, damaged by British accusations that Moscow's security services were complicit in the poisoning of former Russian intelligence officer, Sergei Skripal, in Salisbury.

The UK government has also come under pressure to look at the influence of Russian money and business figures in the British economy.

After the Skripal poisoning, which saw Britain expel 23 diplomats, Theresa May's government said it was reviewing the visas of 700 wealthy Russians who entered the UK on investor visas.

A spokesman for the British Prime Minister yesterday said the government could not comment on why Abramovich's visa had yet to be renewed.

Tom Tugendhat, chairman of UK Parliament's Foreign Affairs Committee told the BBC that he felt the government was "taking much more seriously the threat of corruption from Russia, which is no longer just a financial crime, but is a national security issue".

Andrey Kortunov, director-general of the Russia International Affairs Council, also told the BBC that diplomatic expulsions earlier this year had slowed the processing of visas and Abramovich may simply be part of the backlog.

Abramovich, who owes his US$14 billion (S$18 billion) fortune to investments in Russian metals and oil industries, bought Chelsea in 2003 for £140 million (S$252 million), and is among the most prominent Russian tycoons living in the UK.

BLOOMBERG