War-torn Ukraine on Saturday distanced itself from an EU-brokered agreement with Russia that would have restored its gas supplies during winter and helped rebuild trust between the neighboring foes.

The European Union's energy commissioner emerged from hours of acrimonious negotiations in Berlin on Friday to pronounce the three month dispute on the verge of being resolved.

Ukraine's president may have ordered the closure of his nation's border with Russia but, when asked about it, the rebel commander of this crossing point just smiles and points to the snaking queue of cars traversing the international line.

"As you can see, it is very much open," the border post commander at Uspenka who identifies himself by his nickname "Arshi" says.

Russia is ready to resume gas deliveries to Ukraine if Kiev pays its energy giant Gazprom back debts worth $3.1 billion (2.4 billion euros) by late December, European Energy Commissioner Guenther Oettinger said Friday.

According to the interim agreement, which has to be approved by the governments in Moscow and Kiev, Gazprom is ready to deliver at least five billion cubic meters of gas in the coming months, Oettinger said after he met with both energy ministers in Berlin.

Forensic experts have identified 251 of the 298 passengers and crew killed on downed Malaysia Airlines flight MH17, after 26 people were named this week, Dutch authorities said on Friday.

"Among the 26 victims, 19 were Dutch and seven were of other nationalities," the justice ministry said in a statement, adding that those nationalities would not be released at the request of their embassies.

The European Union said Friday that Russian President Vladimir Putin had written to Brussels demanding changes to a landmark EU-Ukraine accord, but it ruled out reopening the deal without Kiev's consent.

Putin's letter to European Commission chief Jose Manuel Barroso reportedly threatened retaliatory measures if the EU and Ukraine do not stick to their agreement with Moscow to delay the implementation of the deal until 2016.

A U.N. team aims to travel to an area near Donetsk in eastern Ukraine to look into reports of the discovery of a mass grave, a spokeswoman said Friday.

"Our team on the ground is going to investigate," Ravina Shamdasani, spokeswoman for the U.N. human rights agency, told reporters in Geneva.

Pro-Russian separatists in eastern Ukraine and authorities in Kiev are planning to hold talks on energy in the region as winter looms over the strife-torn territory, a separatist leader told Agence France-Presse Thursday.

"These discussions will be about vital infrastructure, including about coal and electricity," Andrei Purgin, deputy prime minister of the self-proclaimed Donetsk People's Republic, told AFP by phone. "They need our coal."

Russia is acting like a "terrorist" in Ukraine and in its intimidation of other neighbors, Lithuania's President Dalia Grybauskaite said in an interview released Thursday.

"I think that Russia is terrorizing its neighbors and using terrorist methods," she told the Washington Post newspaper, replying "Yes" when asked whether she thought both Russia and the Islamic State (IS) group, which is sweeping across Syria and Iraq, were terrorists.

Leaders of the world's most developed economies Thursday warned Russia of more sanctions unless all fighting stops in Ukraine and vowed to stand by the war-torn country as winter approaches.

"Sanctions are not an end in themselves; they can only be rolled back when Russia meets its commitments related to the ceasefire and the Minsk agreements and respects Ukraine’s sovereignty," G7 leaders said after talks in New York.

A Ukrainian doctor and his wife have been kidnapped in the eastern Libyan city of Benghazi, a stronghold of Islamist militias, the Libyan health ministry said Thursday.

The ministry issued a statement denouncing the abduction as an "irresponsible act" and calling on the kidnappers to release the pair who worked at the city's Al-Houari hospital.