BRISBANE, Australia – President Obama edged closer to describing Russia's military incursions in Ukraine as an invasion, saying Sunday that the Western campaign to isolate Moscow would continue, though additional sanctions were unnecessary for now.

Speaking to reporters at the end of the annual meeting of the Group of 20, Obama said the Russians were supplying heavy arms to separatists in Ukraine in violation of an agreement Russia signed with Ukraine a few weeks ago.

"We're also very firm on the need to uphold core international principles," he said, "and one of those principles is you don't invade other countries or finance proxies and support them in ways that break up a country that has mechanisms for democratic elections."

Obama, who met Russian President Vladimir Putin at an economic meeting in Beijing last week and again at the summit here, said he warned him that if the Russians did not change course in Ukraine, "the isolation that Russia is currently experiencing will continue." He described the exchanges as typically "businesslike and blunt."

The president's words were among the toughest he has used about Russia's actions during the Ukraine crisis. But after meeting with European leaders to discuss next steps, it was unclear whether the allies had the stomach for more sanctions.

Putin got a chilly reception from several leaders, including from Prime Minister Tony Abbott of Australia and Prime Minister Stephen Harper of Canada, who told him, "I guess I'll shake your hand, but I have only one thing to say to you: You need to get out of Ukraine."

new york times