North Korea’s communist party boss, Kim Jong-un, touring Russ military facilities in the Far East, may not be getting all the high-tech materiel he’s hoping to receive from President Putin.

It’s one thing to go shopping for planes and ships. It’s another thing, though, to look for the latest in high tech. The head of the UN International Atomic Energy Agency, Rafael Mariano Grossi, doubts that Mr. Putin would share the nuclear technology Mr. Kim might like for his own nuclear warheads.

That North Korea dropped out of the nuclear non-proliferation treaty in January 2003 should be enough for Russia to hang back on aiding and abetting Pyongyang’s nuclear program, in Mr. Grossi’s view. He marked that point in an interview with South Korea’s Yonhap News.

The UN’s non-proliferation official said: “I cannot conceive that countries would engage in trade or in exchanges of nuclear weapons technology with a country that has such a problematic relation with the nonproliferation regime,” as does North Korea. 

Although Mr. Grossi’s remarks did not go beyond North Korea’s nuclear program, the absence so far of a specific agreement between Russia and North Korea gives rise to questions as to whether the Russians would bequeath other highly sophisticated technology that Mr. Kim would love to have.

At the least, the Russians are assumed to be insisting that North Korea ship artillery shells for Russian forces in Ukraine. The need for shells is seen as the top priority of the meeting that Mr. Putin hosted for Mr. Kim at the Vostochny Cosmodrome.

That Mr. Putin personally escorted him around the base from which the Russians launch satellites into orbit was seen as a sign that Russia could provide the expertise for North Korea to launch its own satellites. North Korea has failed in two previous attempts this year to get a satellite into orbit.

“The visit to the space station is very ominous,” a leading expert on North Korea, Victor Cha, who is in charge of the North Korean program at the Center for Strategic and International Studies at Washington, said. “It’s pretty clear they’re looking for technology for satellites.”

The Russians are believed to be hesitant to shower North Korea with all that Mr. Kim wants in view of the certainty of negative repercussions worldwide. Even the Chinese Communist Party, seemingly on the side of Russia and North Korea against America and Japan, may not be happy to see Moscow gaining such influence in North Korea, which depends on China for most of its oil and much of its food.

Mr. Putin may also hesitate in the face of rising threats from Washington and its South Korean ally. Top American and South Korean officials on Friday warned Moscow against a blatant violation of the UN sanctions, barring dealing with North Korea, that Russia had signed before its invasion of Ukraine.

At the fourth annual meeting of the Extended Deterrence Strategy and Consultation Group, two American aides, Bonnie Jenkins and Sasha Baker, joined their South Korean counterparts in warning against Russian cooperation on the North’s nuclear and ballistic programs and North Korean “assistance in Russia’s war effort in Ukraine.”

The American aides assured South Korean officials of America’s commitment to use “the full range of U.S. defense capabilities, including nuclear, conventional, missile defense and other advanced non-nuclear capabilities to provide extended deterrence” for South Korea. 

The sense was the Americans were challenging the Russians, almost daring them, in an exercise in brinkmanship that could raise the danger of the Russians having to support North Korea in a war on the Korean peninsula.

Mr. Kim also apparently is looking for fighter planes to replace the ones his country received from the former Soviet Union in the 1960s and 1970s. On Friday, his armored train stopped at the city of Komsomolsk on the Amur River long enough for a tour of an aircraft factory. In one photograph he’s seen peering into the cockpit of a Sukhoi fighter. In another, he’s gazing at one in flight.

Mr. Kim will be visiting other Russian cities in a tour that should wind up at the seaport of Vladivostok for a look at the Russian Pacific fleet. He may well want Russian assistance in building warships, including a nuclear-powered submarine. 

 Russia, it seemed, was showing off its assets, advertising all that it might offer provided Mr. Kim fulfilled his side of the bargain. “All this time North Korea has been the supplicant,” Mr. Cha said, meaning the North has been asking Russia for aid without much to offer in return. “Now they have the reverse.” 

Mr. Grossi, though, told Yonhap he believed the Russians would still recognize the need to oppose North Korea’s nuclear program. In keeping with Russia’s role as a permanent member of the UN Security Council, “I pretty much hope that this will continue to be the case,” he said, despite “very concerning” signs that North Korea was ready to conduct its seventh underground nuclear test.

The North Korean nuclear program, he warned, was “completely out of any supervisory control, any interaction with any independent monitoring authority or expertise in nuclear safety.”