KIEV, Dec. 26 - The Ukrainian government on Wednesday approved state guarantees for Naftogaz Ukrayiny, the national oil and gas company, to allay concerns among foreign investors holding $500 million in the company’s eurobonds.

The measure, coupled with recent appointments at Naftogaz and at the Energy and Fuel Ministry, is aimed at improving finances of the company, the key shipper of Russian natural gas to the European Union.