The United States is concerned about growing defense cooperation between North Korea and Russia, a National Security Council official said Wednesday, adding the US will take appropriate steps if necessary to counter any potential arms deal between the two countries.

John Kirby, NSC strategic communications coordinator, underscored that Russian support for North Korea's illicit nuclear and ballistic missile programs would be of "significant concern" to the US.

"In a similar fashion to the concern we already expressed about the burgeoning defense relationship between Iran and Russia, we obviously have concerns about any burgeoning defense relationship between North Korea and Russia," Kirby told a press briefing at the White House as North Korean leader Kim Jong-un held a rare bilateral meeting with Russian President Vladimir Putin in Russia.

Pyongyang and Moscow have yet to release details of the Kim-Putin meeting but said Russia will help North Korea develop satellites.

"Certainly, any arrangement that would improve North Korea's military capabilities certainly would be of significant concern to us," Kirby told the press briefing.

The NSC official said the US does not have full visibility on the outcome of the Kim-Putin meeting, but noted Russia is seeking to sign a potential arms deal with North Korea.

"What's going on in the Donbas and down in the south (of Ukraine) is a gunfight as you've heard me say before -- heavily dependent on artillery. So it's entirely likely that that's at least one type of ammunition that Mr. Putin is seeking," he said.

"I have said on the record a week or so ago that we expect there could be other types of munitions, but we just don't have perfect visibility on that," added Kirby.

He also warned of possible consequences for North Korea, saying, "If they decide to move forward with some sort of arms deal, obviously, we will take a measure of that and we will deal with it appropriately."

"As I have said before we continue to urge North Korea to meet its public commitments not to support Russia's war on Ukraine. No nation on the planet, nobody should be helping Mr. Putin kill innocent Ukrainians," Kirby added.

Secretary of State Antony Blinken reiterated that any weapons deal between Pyongyang and Moscow would violate numerous United Nations Security Council resolutions.

"Of course, the relationship between Russia and North Korea that's moving forward now is in violation of numerous UN Security Council resolutions," Blinken was quoted as saying in a Podcast interview.

"We are looking to make sure that we, as necessary, can impose costs and consequences," he added, according to the state department.

Blinken also highlighted US efforts to disrupt any transfer of weapons technology from Russia to North Korea.

"We also don't want to see North Korea benefiting from whatever technologies it might get from Russia," he said. "We are working with other countries; we are taking our own actions to try to disrupt as much of that as we possibly can."

State department spokesperson Matthew Miller characterized the Kim-Putin meeting as the Russian president "begging" Kim for assistance.

"Now a year and a half later after losing tens of thousands of Russian soldiers and spent billions and billions of dollars, he is begging Kim Jong-un for help," Miller told a press briefing. "So, it says something about the overall context of how this war is going for Russia."

Miller added that Putin is "scrounging around the world."

"I don't think at the beginning of this war, Vladimir Putin would have anticipated a year and a half in, he would be having to be scrounging around the world, including with international pariahs, like Kim Jong-un, asking for assistance, and potentially in return having to provide assistance to the DPRK that would violate UN Security Council resolutions that Russia itself voted for," he said.

DPRK stands for the North's official name, the Democratic People's Republic of Korea.

The spokesperson also reiterated that the US will watch "very closely" the development from the summit and will not hesitate to impose sanctions "if it's appropriate." (Yonhap)