KIEV Ukraine's state-run gas transport monopoly Ukrtransgaz has strengthened security on Ukrainian gas pipelines after discovering attempts had been made to tamper with them, the company said on Thursday.
The company, which transports Russian gas through Ukrainian territory to European consumers, said it had found small gas leaks at a transit pipeline in the western part of Ukraine.
Ukraine is an important transit country for Russian natural gas supplies to the European Union. Ukrtransgaz said the leak did not affect gas transit to Europe, but a local prosecutor had launched a criminal investigation.
"During the past few days in western Ukraine several cases of tampering by unauthorized persons in the functioning of gas pipelines have been documented. They have been localized and did not affect gas supply under existing contracts," the company said.
Ukrtransgaz said Ukrainian state security forces and police would help the company guard pipelines. Ukrainian authorities have said they would guarantee stable and safe transit of Russian gas to Europe.
Russia's seizure of Crimea has resulted in EU and U.S. sanctions and triggered fears of Russian gas supply cuts that could affect several European countries.
Ukraine, dependent for more than half of its gas needs on Russia, has refused to pay at the price Russia is asking, accusing Moscow of using energy supplies "politically" to punish the country for trying to break free from its influence.
Moscow and Kiev took tentative steps on Thursday towards ending their standoff over the price of Russian gas supplies to Ukraine that has threatened to disrupt onward deliveries to western Europe.
(Reporting By Pavel Polityuk; editing by Susan Thomas)