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KIEV, May 28 (Reuters) - A company controlled by Ukrainian tycoon Dmytro Firtash said on Thursday it was closing down its last two nitrogen fertiliser plants in Ukraine because of "unprecedented pressure" from the government which had deprived the plants of gas.
A statement by his Group DF said the closure of the Cherkassky Azot and Rivneazot plants would have an effect on grain sowing in autumn and threaten thousands of jobs.
Firtash, one of Ukraine's most influential oligarchs, whose businesses thrived under ousted pro-Russian president Viktor Yanukovich, escaped extradition to the United States last month when an Austrian court accepted his argument that U.S. efforts to try him on corruption charges were politically motivated.
But, amid a campaign by Kiev's pro-western government aimed at ending monopolies and weakening the political influence of the oligarchs, Firtash's businesses have stayed in the cross-hairs of the government and the state prosecutor.
The statement said that Group DF's holding company Ostchem had come under "systematic and unprecedented" pressure from Prime Minister's Arseny Yatseniuk's party.
It added that trumped-up criminal charges against some of Ostchem's executives had led to gas supplies being cut off, leaving the company with no other choice than to close the two factories.
A year ago, two other of Ostchem's plants had been shut down in the east of the country because of the separatist conflict there.
"Cherkassky Azot and Rivneazot have been closed. Autumn grain sowing will be under threat and many thousands of Ukrainians will be left without work," it said.
It described recent moves by the interior ministry against Group DF's holdings as "cynical" and politically motivated. (Writing By Richard Balmforth; Editing by Andrew Heavens)