Russia's membership to the Group of Eight has been suspended over Moscow's annexation of Crimea and its interference in Ukraine, the Group of Seven leading industrial nations said in a statement.
"This Group came together because of shared beliefs and shared responsibilities. Russia's actions in recent weeks are not consistent with them," the leaders of the U.S., Canada, Japan and Europe's four strongest economies said in a statement published Monday on the White House website.
The seven nations have also withdrawn from a G8 meeting that had been planned to take place in Sochi in June, said the statement issued after a G7 summit in The Hague.
"International law prohibits the acquisition of part or all of another state's territory through coercion or force," the statement said. "To do so violates the principles upon which the international system is built. We condemn the illegal referendum held in Crimea in violation of Ukraine's constitution."
"We also strongly condemn Russia's illegal attempt to annex Crimea in contravention of international law and specific international obligations. We do not recognize either," the statement added.
Russian Foreign Minister Sergei Lavrov, on the sidelines of a nuclear security summit at The Hague, brushed off his country's exclusion from the group of leading industrialized nations.
"If our Western partners believe that this format has exhausted itself, then that's the way it is going to be. We don't cling to it," Lavrov said, Itar-Tass reported.
He also said that Moscow did not care if the West did not "believe" that Russia supposedly had no plans to advance further into Ukrainian territory, or that the annexation of Crimea was needed to protect ethnic Russians on the peninsula.
"We are not forcing anyone to believe us," Lavrov said, adding that Moscow did not believe the West either.
"We believed our Western partners for a very long time, starting with the collapse of the Soviet Union, when all kinds of promises were made both orally and in writing, and in the form of political obligations at the highest level. So we can imagine the approximate value of the promises from our Western partners," he said.
He also reiterated Moscow's statements that the dispatch of troops to Crimea and the subsequent annexation was intended to prevent bloodshed.
Following the deployment of Russian troops in Crimea, at least two Ukrainian soldiers have been killed, the Ukrainian Defense Ministry has said. An activist from the Crimean Tatar community has also been found dead, with marks of torture on his body, and several journalists have reportedly been beaten.
The G7 statement said that its leaders "remind Russia of its international obligations, and its responsibilities."
"Russia has a clear choice to make. Diplomatic avenues to de-escalate the situation remain open, and we encourage the Russian government to take them," it said.