Ukraine has still refused to give the green light to a deal that appeared to been reached with Moscow during the previous round of talks in Berlin on September 26, they said.
The new talks are due to take place on Thursday or Friday in Brussels, sources close to the matter told AFP on condition on anonymity.
Ukrainian Energy Minister Yuriy Prodan is due to arrive on Thursday in Brussels for bilateral talks with EU energy commissioner Guenther Oettinger, while his Russian counterpart Alexander Novak is due in the Belgian capital the same day, the sources said.
After the Berlin talks, EU energy commissioner Guenther Oettinger said a compromise deal would see Russia ship at least 5.0 billion cubic metres of gas to Ukraine over a six-month period in exchange for an early payment of USD 3.1 billion (2.4 billion euros).
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But Russia said the $3.1 billion would be used to cover a USD 5.3-billion debt Ukraine incurred last year due to both its financial problems and a refusal to pay the higher rate, and it would eventually also have to pay for the new gas.
"No final decision was adopted. Not a single document was signed -- period," Naftogaz state energy firm chief Andriy Kobolev wrote in a Facebook post.
The gas dispute has frayed nerves not only in Kiev but also in Brussels ahead of the winter, as some eastern EU members are largely dependent on Russian gas pumped through Ukraine.