Russia has gone back on its promise to secure its border with Ukraine against further infusions of weapons and fighters, with at least three Russian tanks and several armored vehicles spotted Thursday in the eastern Ukraine town of Snizhnye, a top Ukrainian official said.
"Columns of armored personnel vehicles and artillery have entered through checkpoints seized by terrorists," Interior Minister Arsen Avakov said at a news conference in Kiev, the capital, citing his nation's intelligence sources and referring to separatists in the east.
Avakov said Ukrainian troops engaged the Russian convoy and destroyed some of the armor.
News agencies in the region also reported sighting Russian tanks for the first time since rebels took up arms against the Ukrainian government in March.
Dmitry Tymchuk, head of the Kiev-based Center for Military and Political Research, wrote on his Facebook page that an armored convoy was seen heading for Donetsk, the largest city held by the rebels.
Russian President Vladimir Putin had promised Ukraine's newly elected president, billionaire Petro Poroshenko, to collaborate in sealing the Ukraine-Russia border to prevent arms and mercenaries from crossing into the fight. The two leaders met in Normandy a week ago on the sidelines of ceremonies marking the 70th anniversary of the D-day invasion.
In Moscow, the official Itar-Tass news agency reported that Putin and Poroshenko spoke by telephone Thursday but made no mention of the reported military hardware sightings. The news agency quoted Kremlin spokesman Dmitry Peskov as saying the two leaders discussed Poroshenko's plan for bringing an end to the armed confrontations in eastern Ukraine but gave no details.
Poroshenko's spokesman, Svyatoslav Tsegolko, reported via Facebook that the Ukrainian president called the armored intrusion "unacceptable."
Ukrainian Foreign Minister Andriy Deshchytsia said at a news briefing in Kiev that the Ukrainians were waiting for Moscow's response to Poroshenko's proposals for countering the separatists who have seized control of much of the Donetsk and Luhansk regions along the border.
"The contact group has met. It worked out conceptual approaches toward implementation of this plan. We are now waiting for Russia's response," Deshchytsia said, referring to several meetings this week of negotiators from Russia, Ukraine and the Organization for Security and Cooperation in Europe.
Vasily Krutov, head of the Ukrainian military operation to push back the separatists, told the online newspaper Ukrainskaya Pravda that measures were being taken "to ensure the border closure in the next few days."
Special correspondent Loiko reported from Moscow and Times staff writer Williams from Los Angeles.