SEOUL, South Korea (AP) — South Korean President Moon Jae-in says the global diplomatic push to defuse the nuclear standoff with North Korea is at a “critical crossroads” and has called for China to continue serving a “positive role” in denuclearizing the Korean Peninsula and stabilizing peace.

Moon made the comments on Thursday during a meeting with Chinese Foreign Minister Wang Yi. He made his first visit in four years amid efforts to patch up relations damaged by South Korea’s deployment of a U.S. anti-missile system China perceives as a security threat.

U.S.-led nuclear negotiations with North Korea have faltered over disagreements in exchanging sanctions relief and disarmament.

North Korean leader Kim Jong Un has issued an end-of-year deadline for the Trump administration to offer mutually acceptable terms for a deal to salvage the diplomacy.