Roman Abramovich, the Russian billionaire who owns London\u2019s Chelsea Football Club, is unable to travel to the U.K. at the moment because of delays renewing his visa, according to people familiar with the situation. Abramovich, who didn\u2019t watch his team win the FA Cup at Wembley Stadium on Saturday, hasn\u2019t been denied a visa, but renewal is taking longer than usual, the people said, asking not to be identified discussing a private matter. Britain\u2019s Home Office, which oversees the country\u2019s immigration service, declined to comment. Although the reason for the delay isn\u2019t clear, the tycoon\u2019s visa trouble comes at a tense time in U.K.-Russian relations, damaged by British accusations that Moscow\u2019s security services were complicit in the poisoning of former Russian intelligence officer, Sergei Skripal. The government has 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, the government said it was reviewing the visas of 700 wealthy Russians who entered the country on investor visas. Tom Tugendhat, Chairman of Parliament\u2019s Foreign Affairs Committee, declined to comment directly on Abramovich, but told the British Broadcasting Corp. that he believed the government was \u201ctaking much more seriously the threat of corruption from Russia, which is no longer just a financial crime, but is a national security issue.\u2019\u2019 Abramovich, who owes his $14 billion fortune to investments in Russian metals and oil industries, bought Chelsea in 2003 for 140 million pounds ($188 million) and is among the most prominent Russian tycoons in British life. He invested about 700 million pounds in new player signings over the following ten years to help the Blues become London\u2019s top team, winning four Premiership titles as well as Europe\u2019s most coveted trophy, the Champions League, in 2012. In the early part of his tenure, the crowd used to join in with the singing of Kalinka, one of the best known Russian songs, while Abramovich clapped along from his box rather sheepishly. The song isn\u2019t sung any more and Abramovich attends fewer games than he used to. Andrey Kortunov, director-general of the Russia International Affairs Council, told the BBC that diplomatic expulsions earlier this year had slowed the processing of British visas in Russia, meaning Abramovich may simply have been caught in the backlog.