North Korea’s leader, Kim Jong Un, peeked his head into the cockpit of a fighter jet at a factory in the Russian Far East on Friday as he pressed ahead on a multiday tour of Russia that is enticing him at each stop with off-limits military technology.

Although Russia’s president, Vladimir Putin, hasn’t promised Kim any of the weaponry and has vowed to abide by United Nations sanctions banning their transfer, the tour carried an implicit threat – an example of what analysts say is a growing danger posed by Putin’s increasingly warm relationship with authoritarian leaders who can pose problems for the West.

At the same time, according to U.S. officials, Putin is cultivating new sources of arms and munitions for his war against Ukraine.

“I think it’s really serious,” said Andrea Kendall-Taylor, a senior fellow at the Center for a New American Security, who previously led analyses of Russia by the U.S. intelligence community.

“It’s not just that it helps Russia mitigate Western pressure and sustain the war in Ukraine,” Kendall-Taylor said. “The more important consequence is Russia is actually amplifying other challenges that the United States faces.”

The Russian president is ever more loudly casting himself as the leader of a global resistance to the United States. Putin has embraced the ayatollah in Iran. He has cruised the Neva River in St. Petersburg, Russia, with African autocrats. He has sat side by side in the Kremlin making small talk with Syria’s leader, Bashar Assad. His efforts crescendoed this week as he hosted Kim, the leader of one of the world’s most repressive and militarized governments, and one with missiles capable of hitting the United States.

In an appearance Friday alongside another dictator aligned against the West, President Alexander Lukashenko of Belarus, Putin said Washington’s belief that it is exceptional was “the main problem of today’s international relations.” He presented himself as the leader of a charge to end what he regularly calls a unipolar world dominated by the United States.

“Some people call it an axis of authoritarians. You could also call it the axis of the sanctioned,” said Hanna Notte, director of the Eurasia Nonproliferation Program at the James Martin Center for Nonproliferation Studies.

This article originally appeared in The New York Times.