Russia has sent thousands of additional troops to its border with Ukraine following the Kiev leadership's announcement that it will sign an economic association pact with the European Union next week.
The NATO chief reporting the renewed Kremlin troop buildup called it "regrettable" and warned that it might be a prelude to an invasion by Russia should the separatist rebellion fail to wrest from Kiev's control the Russian-speaking regions of eastern Ukraine, where vital military hardware is produced for Russia.
It was the decision by then-President Viktor Yanukovych to scrap the European Union association agreement in November that ignited rebellion in Ukraine. Pro-Europe demonstrators angered over his move to keep Ukraine in Russia's economic orbit ousted Yanukovych in February, setting off Russia's seizure of the Crimean peninsula and the separatist battles raging in eastern Ukraine.
Russian President Vladimir Putin warned in an address to agricultural industry leaders on Wednesday that Ukraine's refusal to join the Russia-led Eurasian Union — the economic alliance he created to rival the EU — threatened the customs-free trade between the two former Soviet republics, especially imperiling the market for farm products.
"This doesn't have anything to do with politics or with the options one or another state selects, because each sovereign state has the right to choose its original pathway," Putin said in an apparent attempt to pre-empt Western accusations that he was trying to pressure Kiev to abandon alliance with the Western European bloc.
But Putin's comments followed by mere hours Ukrainian President Petro Poroshenko's announcement that he would sign the economic pact on June 27 during a Ukrainian-EU summit in Brussels.
Putin "stressed Russia's right to defend its own economic interests," the Voice of Russia said of the Kremlin leader's address to an agricultural forum in the southern farm belt center of Stavropol.
Russia maintained more than 40,000 troops along its border with Ukraine over the past three months but had reportedly begun withdrawing them to their bases ahead of Poroshenko's June 7 inauguration. However, NATO Secretary General Anders Fogh Rasmussen said during a London visit Thursday that the alliance has observed a fresh buildup of thousands of additional troops along the border.
"I consider this a very regrettable step backward. It seems Russia keeps the option open to intervene further in Ukraine," Rasmussen said in an exchange with journalists after a speech at London's Chatham House think tank. He warned that NATO "would have to respond in a firm manner" if Moscow further interferes in the conflict convulsing eastern Ukraine.