Russian President Vladimir Putin said Tuesday that North Koreans would rather "eat grass" than suspend a nuclear weapons program that has prompted the Trump administration to call for the toughest possible sanctions against Kim Jong Un's isolated nation.

The Russian leader made the comments at an economic summit in China, where he also warned that the escalating North Korean crisis could cause a “planetary catastrophe” and "huge loss of life."

Putin said "ramping up military hysteria in such conditions is senseless" and called for a diplomatic solution to a standoff between President Trump and Kim that has heightened fears of a military confrontation.

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Putin said North Korea's apparent detonation of a powerful hydrogen bomb Sunday — its sixth and most powerful nuclear test to date — was a "provocative" act. Even so, Putin said Russia views any attempt by the United Nations to impose additional sanctions on North Korea as "useless and ineffective" because Kim feels gravely threatened by the West.

"They will eat grass but will not stop their program as long as they do not feel safe," Putin said, perhaps deliberately using words that reflect that North Korea has suffered from famine and food shortages, although its state media have portrayed Kim's efforts to join the nuclear club as a major achievement of his regime.

Russia is itself the target of U.S. and European sanctions for its alleged meddling in the 2016 U.S. election, for its illegal annexation of Ukraine's Crimea and for various human rights violations. Moscow routinely says these sanctions have no impact.

Putin said that only diplomacy would solve the crisis.

His intervention comes after the U.N. Security Council held its second emergency meeting about North Korea in a week on Monday, with U.S. Ambassador Nikki Haley saying the North's actions show that Kim is "begging for war" and that stronger diplomatic measures were needed.

"Enough is enough. War is never something the United States wants. We don't want it now. But our country's patience is not unlimited," Haley said.

She did not elaborate on what type of additional measures could be taken.

North Korea is already subject to sanctions that target its exports of some commodities and its access to international banks is severely restricted. There could be further travel bans on North Korean diplomats or large-scale asset freezes.

German Chancellor Angela Merkel and Japanese lawmakers urged the U.N. on Tuesday to strengthen sanctions on North Korea, a move that could happen by early next week. Taro Kono, Japan's foreign minister, said loopholes that allow some countries, such as China, to continue trading with Pyongyang need to be eliminated.

President Trump has also pressured Beijing in recent days by threatening to stop U.S. trade with China. China is the U.S.'s largest trading partner.

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