KIEV, Jan. 28 – Heat supplies have been cut off in some regions of Ukraine, because the state needs money for the national gas company Naftogaz Ukrainy to return 12.1 billion cubic meters of gas to the Swiss-registered gas trader RosUkrEnergo AG, according to leader of the Batkivschyna All-Ukrainian Union and former Prime Minister Yulia Tymoshenko.

"The thing is that it has been more than two months since Naftogaz... started paying money to the shadowy company RosUkrEnergo," the former prime minister told journalists on Thursday before entering the Prosecutor General's Office.