China dismissed a report that North Korea is continuing to upgrade a missile manufacturing facility, touting instead the “momentum” behind the denuclearization process.

“I don’t know where they come from or on what basis those U.S. officials made the relevant comments,” Foreign Ministry spokesman Lu Kang said. “I think you may have to seek clarification from them.”

Nongovernmental researchers have concluded that North Korea has been proceeding with construction at a plant that produces ballistic missiles “as well as re-entry vehicles for warheads” that could reach the United States, the Wall Street Journal reported. That analysis is based on satellite imagery. Other U.S. intelligence officials reportedly have acquired information that North Korea is “exploring ways to deceive Washington” and avoid dismantling the full program.

“China always supports the DPRK and the ROK in improving their relations,” Kang said, using the respective formal acronyms for North and South Korea. “We also hope that the international community can root for the two sides and play a constructive role in sustaining the momentum for dialogue, advancing the denuclearization of the Korean Peninsula and moving forward the political settlement process of the Korean Peninsula issue.”

As North Korea’s chief patron, China has broad influence over whether the regime feels the kind of sanctions pressure required to induce dictator Kim Jong Un to denuclearize. But Republican and Democratic lawmakers are wary of China’s role in the talks — suspicious that Chinese President Xi Jinping is using the nuclear crisis to try to diminish the U.S. military presence in the region.

“I suspect that maybe President Xi, behind the scenes with Kim Jong Un, is saying, 'Listen, you give this crap up, but what you have to get for it is, you got to get the U.S. to pull out; that’s your price for complete denuclearization,’” Senate Homeland Security and Government Affairs Chairman Ron Johnson, R-Wis., told the Washington Examiner.

Xi and Kim have met three times in the months since President Trump agreed to have a summit with the North Korean dictator, including one after the summit in Singapore. A senior member of Kim’s government is also traveling in Beijing. “China and the DPRK are friendly neighbors and our two sides maintain normal exchanges at all levels and in various areas,” Kang said.