Britain on Thursday condemned what it called Russia's decision to use ballistic missiles sourced from North Korea in recent attacks against Ukraine.

"The UK strongly condemns Russia’s decision to use ballistic missiles sourced from North Korea in recent attacks against Ukraine," the UK's Foreign Office spokesperson said in a statement. "We urge North Korea to cease its arms supply to Russia."

The reaction followed the White House, citing newly declassified intelligence, saying that North Korea recently provided Russia with ballistic missiles and launchers for use in Moscow's war against Ukraine, some of which Russia has fired into Ukraine.

U.S. national security spokesperson John Kirby also said that the United States will raise the development with the United Nations Security Council, and would impose additional sanctions against those facilitating the arms deals, while calling North Korea's arms transfer to Russia a "significant and concerning escalation."

North Korea is subject to a robust sanctions regime, the UK Foreign office spokesperson said.

"UK will continue to work with its partners to ensure that North Korea pays a high price for supporting Russia's illegal war in Ukraine."