U.S. Secretary of State John Kerry has told Chinese President Xi Jinping that now is a "critical time" as the two men discuss North Korea's nuclear program and other issues.
Kerry is meeting with President Xi in Beijing Saturday, as North Korea's East Asian neighbors wait to see if Pyongyang will do as it has threatened and test a nuclear missile.
The top U.S. diplomat has been urging Chinese officials to use their influence as North Korea's strongest ally to influence Pyongyang to back off of its threats.
Kerry also noted that other challenges face China and its neighbors: Iran, nuclear weapons, upheaval in Syria, and economies around the world that need a boost.
In a recent speech, President Xi said - without explicitly naming North Korea - "no country should be allowed to throw a whole region and even the whole world into chaos for selfish gain."
The U.S. secretary of state also met Saturday with Chinese foreign minister Wang Yi, who called for peace, dialogue, and denuclearization on the Korean peninsula.
Officials have warned a North Korean missile test could happen at any time. South Korea says a test could occur as North Korea prepares to celebrate the 101st anniversary of the birth of it's founding leader, Kim Il Sung, on Monday.
Kerry said the U.S. Defense Department is working on the assumption that North Korea is not yet able to place a nuclear warhead on a ballistic missile, despite a U.S. intelligence report suggesting that it does have that capability.
This is Kerry's first visit to the region since becoming secretary of state, but the broader issues he hoped to address have been overshadowed by the North Korean threats.
Russian Foreign Minister Sergei Lavrov said Friday he backs the idea of Switzerland hosting a fresh round of six-nation talks on North Korea's atomic program.
North Korea abandoned the talks in 2009 to protest international condemnation of its long-range missile tests. The United States, Russia, China, Japan and South Korea are involved in negotiations with Pyongyang on closing its nuclear program in exchange for aid and energy.
North Korea has carried out three nuclear tests. The latest, in February, used what the North said was a "smaller and lighter" device. Late last year, it succeeded in using a long-range missile to place a satellite into orbit.