A controversial Ukrainian oligarch had his attempts to return to Kiev for the first time in nearly two years stymied on Wednesday, after the interior minister threatened to have him arrested at the airport by a group of far-right fighters.

Dmytro Firtash, one of Ukraine’s richest men, has not been back to Kiev since he was arrested on a US extradition warrant in Vienna just four days after the culmination of the Maidan revolution last year.

The case was thrown out by an Austrian judge as politically motivated earlier this year, but US authorities are now appealing.

Firtash had planned to return to his home country to address a congress of employers, as well as to regain influence lost in the time he has been away. He was close to former president Viktor Yanukovych, who was ousted in the revolution, and critics have described him as a Russian puppet.

Facebook Twitter Pinterest Dmytro Firtash. Photograph: Leonhard Foeger/Reuters

Firtash denies this, saying he merely believes Ukraine should keep good relations with both the EU and Russia. In an interview with the Guardian in Vienna on Wednesday he strongly criticised the current government and said they were “more corrupt” and “less effective” than the Yanukovych government had been.

Although he does not face any charges in Ukraine, authorities in Kiev have gone to extraordinary efforts in a bid to prevent the billionaire from returning. “I don’t know why they had to create this circus,” Firtash said. “The government just doesn’t want to hear an alternate opinion.”

Ukrainian authorities announced last week they were banning all charter flights from Ukrainian airspace, widely seen as a move to stop the oligarch returning. This led to Firtash and his entourage purchasing tickets on an Austrian Airlines flight for Wednesday morning.

Andriy Biletskiy, head of the far-right Azov group which fought for Kiev in the war in the east of the country, said if the police were unable to arrest Firtash, his men would arrest him. In a statement, Biletskiy called Firtash “the grey cardinal of Russian influence” in Ukraine. “My personal position and the position of Azov is that if one foot of this werewolf should set foot in Ukraine, he should be arrested, and put on trial,” Biletskiy said.

After this statement, Firtash said he decided it was not safe to travel. On Wednesday, the interior minister, Arsen Avakov, posted a photograph on his Facebook page of 10 heavily armed men who were apparently Azov battalion fighters at Kiev’s Borispol airport saying they were “waiting for Firtash”.

“Who are these people? A group of people in masks making threats. In any normal country you would be put in jail for this,” Firtash said.

Firtash and some of his associates were accused by US prosecutors of paying $18.5m in bribes to Indian officials to secure a titanium-mining contract, a deal which in the end never materialised. Firtash denied the allegation.

His lawyers contend the extradition request was politically motivated and designed to keep Firtash out of the country at a sensitive time; US authorities insisted the timing was coincidental. The request for Firtash’s arrest was filed in Vienna by the US on 26 February last year, four days after Yanukovych was ousted in Kiev.

The Austrian judge who presided over the hearing agreed with the businessman and dismissed the request, a decision the US authorities are currently appealing against.