Russia’s largest oil producer, battered by a gigantic overdue back taxes bill, says it may have to halt its main production units within a few days because of a bailiffs’ order, the Interfax news agency reported in Moscow.

Russia’s richest man, ex-Yukos CEO Mikhail Khodorkovsky, has pleaded not guilty to a raft of charges that could jail him for 10 years, while authorities tightened the grip on the beleaguered oil company’s key production assets.

The plain clothes officers who searched the headquarters of the Russian oil giant Yukos, beleaguered by a 99.4bn-ruble (€2.6bn) back taxes claim, were looking for evidence of tax-evasion by a Yukos subsidiary, a company spokesman said today.