President Vladimir V. Putin of Russia has ordered troops into two Russia-backed separatist territories in Ukraine and hinted at the possibility of a wider military campaign and laid claim to all of Ukraine as a country “created by Russia” in an emotional and aggrieved address to the Russian people.

Russian state television then showed Mr. Putin signing decrees late Monday recognizing the so-called Donetsk and Luhansk People’s Republics and directing the Russian Defense Ministry to deploy troops in those regions to carry out “peacekeeping functions.”

The order was condemned as a violation of international law and Ukraine’s sovereignty by several nations at an emergency meeting of the United Nations Security Council on Monday night.

“He calls them peacekeepers,” said Linda Thomas-Greenfield, the U.S. ambassador to the United Nations. “This is nonsense. We know what they really are.”

Ukrainian President Volodymyr Zelenskyy said his country unequivocally sees Putin’s action as a violation of its sovereignty and territorial integrity. It could mean a unilateral withdrawal from the Minsk agreements that sought to end war in the Donbas region, he said.

“All responsibility for the consequences in connection with these decisions rests with the political leadership of the Russian Federation,” Zelenskyy said in an address late Monday.

“We are not afraid of anything or anyone,” he said later in the address, referring to Russia’s presence in Donbas since 2014.

“We owe nothing to anyone, and we will not give anything to anyone,” Zelenskyy said, “and we are sure of that, because now is not February 2014, but February 2022 — another country, another army, one goal — peace, peace in Ukraine. Glory to Ukraine!”

The European Union condemned Putin’s recognition of the two regions in eastern Ukraine “in the strongest possible terms” and vowed sanctions of its own.