The Russian oligarch and owner of Chelsea football club, who is the 13th richest person in Britain with a net worth of £9.3bn, according to the Sunday Times, held an entrepreneurial visa to the UK that expired several weeks ago. He has filed for a new visa, but has not yet been granted one, and it is not clear if or when he will be.

Abramovich was not seen at Saturday’s FA Cup final at Wembley, which ended in a 1-0 victory for Chelsea over Manchester United.

A person who knows Abramovich said he had not been denied a visa, but that it was taking longer than usual to renew and it was unclear why.

A representative for Abramovich declined to comment on the reports, calling it a personal matter.

Anglo-Russian relations have been strained since the double poisoning of the former Russian secret agent Sergei Skripal and his daughter in Salisbury in March. The UK expelled 23 Russian diplomats from the country in March, leading to a tit-for-tat expulsion by Russia later that month.

Russia shut down the activities of the British Council, which promotes cultural programmes between the two countries, and Britain’s consulate-general in St Petersburg. The prime minister, Theresa May, also said the government would look more closely at Russian investments in the UK.

The home secretary, Amber Rudd, said in March that the government would look retrospectively at Tier 1 visas, those given to applicants who want to open businesses in Britain and have at least £50,000 in investment funds, like the one Abramovich held. Nearly 700 Russians came to Britain between 2008 and 2015 on such visas.

The delay in Abramovich’s visa was first reported by the Russian news agency the Bell, which wrote on Sunday that it had expired three weeks ago and that his private Boeing 767 last travelled to London on 1 April. The report cited three people who know Abramovich.

A second person who knows him told the Guardian the report “looked correct”, but emphasised that the Russian businessman had not yet received a firm answer from British authorities.

The UK security minister Ben Wallace said: “We do no routinely comment on individual cases.”

Abramovich bought Chelsea in 2003 and has helped bankroll the club during a period of unprecedented success, including five league titles. He regularly attends the club’s matches at Wembley and was seen at previous cup finals.

Once considered Russia’s richest man, he said in a British court in 2011 that he had an extravagant lifestyle, including properties in London and France and the luxury 533ft super-yacht Eclipse.

The Russian, who does not hold UK residency, owns a £90m home in Kensington Palace Gardens, nicknamed Billionaires’ Row.

He owns Evraz, Russia’s largest steelmaker, and the metals producer Norilsk Nickel. He made his fortune in the 1990s in oil and gas in a period when state assets were privatised and sold off to a number of businessmen who made fantastic fortunes.

Abramovich sold his stake in the oil firm Sibneft to the state-controlled gas group Gazprom for £7.4bn in 2005, increasing the Kremlin’s control over the country’s energy assets.

His stake in the company became the subject of a £2bn lawsuit in a British court. Boris Berezovsky, a once-powerful businessman who lived in self-imposed exile under Putin, sued Abramovich in 2008 over claims that he was forced to sell his shares in Sibneft under the threat of violence. Berezovsky lost the case in 2012.

While Berezovsky fell foul of the Kremlin under Vladimir Putin, Abramovich has maintained good relations with the Russian government. He served as governor, and then as the chair of the legislature in the remote Russian region of Chukotka. He helped build infrastructure at the 2014 Sochi Olympics that became an important prestige project for the Kremlin.

A judge in the Berezovsky lawsuit ruling said that while Abramovich “enjoyed very good relations with Putin and others in power at the Kremlin”, he did not have enough influence to “pull the presidential strings”.

He was named on a list of Russian oligarchs supposedly linked to Putin released by the US Treasury Department earlier this year. But the list was ridiculed as a carbon copy of the Forbes list of all Russians worth more than $1bn. 

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