Russia and Ukraine will resume efforts to resolve a gas pricing dispute late on Tuesday after a Russian deadline for Kiev to pay some of its debts passed without Moscow cutting off supplies.
The gas dispute is at the heart of a crisis between Russia and Ukraine, and failing to resolve it would set back peace moves that are gaining momentum after weeks of violence in east Ukraine.
Russia gave Ukraine until 10 a.m. Moscow time (0600 GMT) on Tuesday to pay some of the billions of dollars it owes, but pulled back from the deadline after officials said talks brokered by the European Commission would continue in Brussels.
Russian Energy Ministry spokeswoman Olga Golant confirmed the Russian delegation was flying back to Brussels for evening talks after consultations with President Vladimir Putin in Moscow. The Russian leader will have the final say on any deal.
The European Commission confirmed negotiations would resume at 9 pm (1900 GMT) after eight hours of talks, which ended early on Tuesday, failed to get a deal.
After annexing Crimea in March following the overthrow of Ukraine's Moscow-leaning president, and facing unpredictable events in east Ukraine, Putin appears to have reason to reduce tension.
Ukraine looks poised to pay more of its debt, but talks have stalled on the price, threatening possible supply disruptions to the European Union, which gets about a third of its gas imports from Russia, almost half of it via Ukraine.
A source at Gazprom said Russia was supplying Ukraine with the usual volumes of gas and levels may have increased recently.
"Ukraine has been taking 112-115 million cubic metres a day, at a peak, as it pumps gas into storage facilities. Transit to Europe remains stable, at 200 million cubic metres per day," the source said.
Talks between Russia, Ukraine and the European Commission have been going on while Kiev, Moscow and the Organization for Security and Cooperation in Europe discuss peace proposals put forward by Ukraine's new president, Petro Poroshenko.
Those talks have produced what Kiev says is a mutual understanding on key aspects of the peace plan, intended to end an insurrection by separatist rebels who want to join parts of Russian-speaking east Ukraine with Russia.
DISAGREEMENT ON PRICE MECHANISM
The talks, which ended early on Tuesday, faltered over the price Moscow would charge Kiev in future.
Ukraine wants to change the 2009 contract that locked Kiev into buying a set volume of gas, whether it needs it or not,