The United States imposed fresh North Korea-related sanctions on Friday, targeting Russian individuals and companies after U.S. and South Korean officials said Pyongyang had used its largest intercontinental ballistic missile (ICBM) system in two recent launches, Reuters reported.

The sanctions, announced by the U.S. Treasury, targeted two Russian nationals and three Russian firms it linked to North Korea's procurement activities for its missile programs.

The measures come amid concerns that North Korea may soon follow through on threats to resume full testing of long-range ICBMs and nuclear weapons for the first time since 2017.

The U.S. Treasury named the Russians as Aleksandr Andreyevich Gayevoy and Aleksandr Aleksandrovich Chasovnikov, both of Vladivostok. It named the Russian firms as Apollon OOO, Zeel–M Co., Ltd, and RK Briz OOO.

"The DPRK continues to launch ballistic missiles in blatant violation of international law, posing a grave threat to global security," U.S. Treasury Undersecretary for Terrorism and Financial Intelligence Brian Nelson said in a statement, referring to North Korea by the initials of its official name.

"Today's actions respond to this threat by targeting a network of Russia-based individuals and entities complicit in helping the DPRK procure components for its unlawful ballistic missile systems," he added.

The sanctions freeze any property held by the individuals or firms in the United States and prohibit business dealings with them.