Both publicly and behind the scenes, Russia has been seeking a greater role for itself in the North Korean nuclear crisis. U.S. officials and experts worry Russian President Vladimir Putin’s unhelpful efforts are driven not by the perceived threat of North Korean leader Kim Jong Un but by a perennial quest to boost Russian prestige and leverage at the expense of America.

The United States, its allies and the North Korean regime all find themselves responding to Moscow’s increased intervention into the already complicated diplomacy. For the Trump administration, sincere Russian help with North Korea would be welcome, but that’s not what it is seeing.

“They want to be at the table, they want to be relevant, they want to have leverage to either play a spoiler role or play a broker role,” a senior administration official told me. “They are definitely up to something.”

The escalation of Russian involvement is easy to see. In China, Putin spoke out strongly against the U.S. plan to increase sanctions on North Korea, following its sixth nuclear test. He said sanctions against North Korea are “useless and ineffective” and suggested the world offer security guarantees to Pyongyang.

“They’ll eat grass, but they won’t abandon their program unless they feel secure,” he said.

Putin’s comments went even further than the Chinese government, which called President Trump’s threat of cutting off all countries that trade with North Korea “unacceptable” but said further sanctions would be debated at the U.N. Security Council.

Privately, Russia has been making a play to insert itself into the back-channel diplomacy, three officials said. Putin’s government recently invited the State Department’s special representative for North Korea policy, Ambassador Joe Yun, to come to Russia for discussions in early September about potential dialogue with North Korea. Yun initially accepted the invitation, but the visit was later postponed and has not been rescheduled.

Russia also invited Choe Son Hui, deputy director general of the North Korean foreign ministry’s U.S. affairs department, to visit Russia later this month, one U.S. official said. The goal is to feel out Pyongyang as to a possible resumption of dialogue between the United States and North Korea. Putin, for his part, will meet with South Korean President Moon Jae-in Wednesday at a long planned conference in Vladivostok.

U.S. administration officials said that dialogue with the Kim regime is not on the table right now, as the White House is focused on increasing pressure on North Korea and working with China to implement the latest Security Council resolution. Yun keeps in regular contact with the Russian government, as part of his job, officials said. But there’s no appetite for elevating Russia’s diplomatic role.

Russia’s principal proposal, which would trade a freeze in North Korea’s nuclear and missile activities in exchange for the United States and South Korea paring down military exercises, is a non-starter for both Washington and Seoul. Experts say Moscow must know this, and its persistence shows that Putin is really more interested in helping Russia assert itself and gain leverage against the United States.

“It gives them an opportunity to highlight the ways in which they can either contribute to or undermine U.S. foreign policy,” said Paul Saunders, executive director of the Center for the National Interest. “From the perspective of their foreign policy, it allows them to take a carrot and sticks approach to Washington.”

The Trump administration has worked with Russia, for example in Syria. But cooperation is extremely difficult given the ongoing investigations into Trump’s ties to Russia and the U.S. sanctions for Russia’s interference in the 2016 election, which have triggered a tit-for-tat diplomatic battle.

If Russia can insert itself as an important player on North Korea, it could use that as a bargaining chip in other areas. Or Putin could use criticism of U.S. sanctions and what he sees as Trump’s belligerent rhetoric to try to drive a wedge between Washington and allies such as South Korea.

“It’s part of Putin’s grand policy,” said Center for National Interest President Dimitri Simes. “Russia posture vis-à-vis the United States is that American behavior is unacceptable and Russia will not accept it.”

To be sure, U.S. and Russian interests overlap. Neither wants to see war on the Korean Peninsula or an unrestrained Kim threatening the region. But unless Putin gets on board with the U.S. strategy, which is to increase pressure on North Korea before contemplating concessions, his increased intervention is unhelpful.

The Trump administration must leave the door open to Russia becoming a part of the solution to the North Korean crisis but recognize the dangers if Moscow is intent on becoming part of the problem.