Ukraine announced on Tuesday the immediate suspension of all Russian gas purchases following a breakdown of EU-mediated price negotiations aimed at keeping supplies running for the next three to six months.

The state energy company Naftogaz said it would still continue transporting Russian gas supplies westward to its other European customers.

"Since the additional agreement between Naftogaz and Gazprom is expiring on June 30, and the terms of further Russian gas deliveries to Ukraine were not agreed at today's trilateral talks in Vienna, Naftogaz is suspending purchases from the Russian company," the Ukrainian firm said in a statement.

It marks the second time in less than a year that Russian fuel supplies have stopped running to its westward-leaning former Soviet neighbour.

Moscow dramatically hiked the price it charges Ukraine for gas in the wake of the February 2014 ouster of Kremlin-backed leader Viktor Yanukovych.

The European Union -- mindful of the repeated price battles because Russia supplies its 28 member nations with about a third of their natural gas needs -- has since been able to forge a series of temporary agreements that need to renewed every three months.

Ukraine is also increasingly relying on gas purchases from central European states.