The owner of Swiss-based oil trader Gunvor has denied that Prime Minister Vladimir Putin's help was key to turning his firm into a global player in an open letter called "Gunvor, Putin and me: the truth about a Russian oil trader."

Gennady Timchenko's letter, published Thursday by the Financial Times, became the first public statement by the mysterious tycoon, who co-owns the world's third-largest trading house.

He was reacting to years of speculation that he enjoyed special ties with former President and current Prime Minister Vladimir Putin.

"Media suggestions about the extent of any ties between me and Mr. Putin are overblown," said Timchenko, who owned a few trading companies in and near St. Petersburg in the 1990s, when Putin worked in the city mayor's office.

Timchenko's partner and Gunvor's co-founder, Torbjorn Tornqvist, denied that Gunvor ever enjoyed Putin's support in an interview in October.

Gunvor handles more than one-third of Russian crude exports, making it the world's second-largest crude trading company. It also handles a big chunk of oil products, with the lion's share coming from state-controlled companies, such as Rosneft and Gazprom Neft.

"It is true that I, together with three other businessmen, sponsored a judo club where Mr. Putin became honorary president. That is as far as it goes — yet time and again, the media wrongly jump to the conclusion that the judo club connection means that Mr. Putin and I are 'close,' then leaps into conspiracy-theory mode," Timchenko said.

The rapid growth prompted speculation that the firm enjoyed special support from the Kremlin, although Gunvor's competitors say the trader often offers healthy premiums to outbids rivals.

"My career of more than 20 years in the oil industry has not been built on favors or political connections. When it comes to price — ask our rivals and study our record in open tenders," Timchenko said.