KYIV, May 16 - Ukrainian tycoon Ihor Kolomoyskiy, the key supporter of Volodymyr Zelenskiy’s campaign to win the presidency, has returned to the country Thursday after almost two years in self-exile, an investigative television program, reported.

Skhemy (Schemes), a joint project by RFE/RL's Ukrainian Service and Ukraine's UA:Pershy television channel, quoted sources at the international airport in the eastern city of Dnipro as saying that Kolomoyskiy had landed there early on May 16.

Kolomoyskiy, one of Ukraine's richest men and a former regional governor, was on board of a private plane coming from Tel Aviv, the sources said.

Kolomoyskiy has been at odds with outgoing President Petro Poroshenko for years.

His return to his home country comes weeks after Zelenskiy defeated Poroshenko in an April 21 presidential runoff election.

The Babel online newspaper quoted Kolomoyskiy as saying after landing in Dnipro that he didn't know about his plans yet.

The billionaire had said he was not afraid to come back to Ukraine, saying he expected what he called political pressure on courts to stop under Zelenskiy's presidency. Zelenskiy is set to be inaugurated on May 20.

Zelenskiy is linked to Kolomoyskiy through the oligarch's ownership of TV station 1+1, which hosts Zelenskiy's comedy programs.

Reporters have also found other links between the two, including shared security details and vehicles, as well as possible meetings abroad in the run-up to Zelenskiy's candidacy.

One of Zelenskiy's top campaign advisers was Kolomoyskiy’s personal lawyer, prompting Poroshenko to claim that the billionaire supported Zelenskiy's campaign financially in order "to take revenge against the state" for the nationalization of PrivatBank.

Kolomoyskiy, who has faced investigations and government pressure in Ukraine, left the country in June 2017 and later split his time between Israel and Switzerland.

Poroshenko has claimed that Kolomoyskiy supported Zelenskiy's election campaign financially in order "to take revenge against the state" for the nationalization of PrivatBank.

The nationalization occurred in December 2016 with the backing of the International Monetary Fund after risky lending practices left it with a capital shortfall of billions of dollars.

Kolomoyskiy, one of the bank's former main shareholders, opposed the move, and a Ukrainian court ruled on April 18 that the nationalization was illegal. Ukraine's central bank is appealing the ruling.

Kolomoyskiy served briefly as governor of the Dnipropetrovsk region before Poroshenko dismissed him in 2015, accusing him of setting up a private militia and trying to take over a state-affiliated oil company.

Kolomoyskiy had been credited with preventing the spread of separatist sentiment in Dnipropetrovsk following Russia's seizure of the Crimean Peninsula in March 2014 and backing of armed separatists further east in the Donbas.

The region he governed borders the Donetsk region, one of the two regions held in part by Russia-backed separatists whose conflict with Kyiv's forces has killed some 13,000 people since April 2014. (rfe/ez)