The photograph is low quality and appears similar to any taken of a group of male friends after dinner in post-Communist Moscow. But contained within this grainy 1994 shot, are some remarkable characters who have suddenly started to fascinate City bankers.

On the bottom right is Andrei Skoch, now rated as the richest man sitting in the Duma, Russia's parliament. He is also a close friend of the billionaire oligarch and Arsenal shareholder Alisher Usmanov and indirectly a leading figure behind MegaFon, the Russian telecoms business that Usmanov jointly listed on the London and Moscow stock markets on Wednesday.

Sitting next to Skoch is Sergei Mikhailov and, next to him on the front row is Viktor Averin. These are said to be two of Russia's most feared gangsters.

These old connections have suddenly resurfaced as MegaFon – which last week announced the appointment to its board of former Labour minister and one time chairman of the Guardian Media Group Lord Myners – began trading 17% of its shares in London. Coincidentally, that is almost the same size of stake indirectly owned by the Skoch family. The shares fell nearly 3% on their first day.

Skoch, who has placed all of his business interests in the name of his father, Vladimir, declined to answer any questions about his connections when approached by the Guardian in Moscow last week. In a response to questions by email, a spokesperson for Usmanov said there have been "too many unwarranted allegations, rumours and speculations about different people in Russia".

However, Skoch was prepared to give an interview to last Friday's Financial Times in which he admitted knowing Mikhailov and Averin. He also previously spoke about the ties in a 2010 interview with the Russian business newspaper Vedomosti, during which he confirmed that the photo was genuine.

He said that he got to know Mikhailov after he and Lev Kvetnoy bought several service companies at Moscow's Vnukovo airport.

Skoch added that he was "introduced" to Mikhailov and Averin as the "owners" of the Vnukovo companies. "We met, discussed terms, and then agreed – the photo was taken afterwards," he said.

Averin subsequently invited him and his wife to a holiday in Prague, in 1995. Skoch was one of 50 guests who celebrated Averin's birthday at the Ritz Hotel. In his Vedomosti interview, Skoch said the guests had been sitting down for 15 minutes over dinner when the Czech police burst in. The police took all the guests down to the station for questioning, photographed them and then let them go. "After that I didn't have any shared history with Viktor [Averin]. Not with him, not with Sergei [Mikhailov]. We didn't have any joint interests," he said.

However, Skoch told the FT last week that he continued to meet Averin for business purposes after the incident, with their last meeting seven years ago when they bumped into each other at a Moscow restaurant. "He's a nice enough guy," he told the paper.

The politician, whose wealth has been valued by Forbes at $4.2bn (£2.6bn), denied that he, Mikhailov or Averin had any links with Russian organised crime. "I can't say they were bandits. They were ordinary businessmen," he told the FT.

"I couldn't say that anyone joined a [mafia] group. That would be incorrect," Skoch also told Vedomosti. In the lawless Russia of the 1990s, he said it wasn't entirely clear "who was in a mafia group and who wasn't". "You'd go into any restaurant and there would be a serious-looking guy sitting there. If you wanted to live, you had to be unafraid," he said.

However, according to Federico Varese, professor of criminology at Oxford University, Mikhailov is the alleged founder of the "Solntsevo fraternity", Russia's most powerful mafia gang.

The group is named after a rundown area of western and southwestern Moscow – the name Solntsevo would translate as Sunnyside in English. Varese dubs the gang "arguably the mightiest organised crime group to emerge from the wreckage of the Soviet Union."

In the same Vedomosti interview Skoch boasts of his close friendship with Usmanov – who has also faced questions about links to Gafur Rakhimov.

Usmanov denies that he has ever had any business dealings with Rakhimov, whom he says was a neighbour of his parents.

Skoch recalled that he met Usmanov in 1995, and went into business, buying a metallurgical industrial complex. The venture succeeded thanks to Usmanov's "intellect", Skoch said, adding: "We are very close. I trust him with my life."

In 2010 Skoch said he saw Usmanov "virtually every day" and had travelled with him to Tashkent when Usmanov had a major operation.

• This article was amended on 29 January 2013 to remove an incorrect reference to Gafur Rakhimov.