Slovakia and Ukraine have agreed a deal that will allow gas from Central Europe to reach Ukraine via Slovakia.
Under the deal Slovakia will reinstate a disused pipeline that will be capable of supplying 3 billion cubic metres (bcm) of gas a year to Ukraine.
Ukraine has been looking for alternatives to Russian gas, which last year accounted for around a half of its 55bcm consumption.
In April, German energy firm RWE began deliveries of gas via Poland.
Under that deal RWE can supply up to 10bcm of gas a year.
Russia has almost doubled the price of gas for Ukraine, following the toppling of pro-Russian President Viktor Yanukovich in February.
Also, Ukraine owes Russian gas firm, Gazprom $2.2bn (£1.3bn) for supplies of gas.
The two nations are in dispute over that debt and Ukrainian officials are concerned that Gazprom could just cut off the nation’s supply of gas.