Chinese President Xi Jinping doesn’t want to negotiate expanding a landmark Cold War nuclear arms control treaty to cover Beijing’s military, a top Communist diplomat said Saturday.

“It would involve a series of complicated political, military and legal issues to make the Intermediate-Range Nuclear Forces treaty multilateral, and many countries remain concerned about this,” Geng Shuang, a Foreign Ministry spokesman, said Saturday. “A higher priority is to maintain and fully implement the existing treaty rather than establishing a new one.”

Geng rebuffed the thought of an expanded treaty on the same day that the President Trump’s administration sent the formal notification to Russia that the United States would withdraw from the INF treaty, which bans ground-based intermediate range cruise missiles. U.S. officials, dating back to President Barack Obama’s administration, have accused Russia of violating the agreement and necessitating the American exit.

“China opposes the U.S. withdrawal and urges the U.S. and Russia to properly deal with disputes through constructive dialogue,” Geng said.

Russia denies violating the pact, but both parties agree that the treaty has the side effect of imposing legal obligations on Russian and American forces while leaving China — which is not a party to the deal — free to develop the otherwise-illicit missiles. U.S. officials assess that Russian President Vladimir Putin’s motives for authorizing the treaty violations stemmed, in part, from concern about Chinese stockpiles.

“For Putin, this is very much about his neighbors, China being one of them,” a senior administration official said Friday while discussing the controversy that led to the U.S. decision to exit. “And while China has significant number of missiles that would be bound by the INF treaty, as Putin noted, they’re not in the treaty. And so, while this is very much about China and other countries for Putin, for the United States, this is strictly about the threats this poses to arms control and the threats it poses to European security.”

NATO worries that Russia’s deployment of the missiles increases the possibility of nuclear war on the continent, by emboldening Kremlin strategists to think they could have a “limited nuclear war” that doesn’t involve the United States.

“The theory is that you can limit a war because you use weapons which are not aimed at or not capable of reaching the United States,” NATO Secretary General Jens Stoltenberg, the civilian head of the alliance, told the Washington Examiner during a Sunday interview. “Any idea about any kind of limited nuclear war is dangerous because it reduces the threshold and it increases the likelihood of any potential use of nuclear weapons in the conflict.”