WASHINGTON — The United States is “concerned” by reports of North Korean soldiers fighting for Russia in Ukraine, a White House spokesperson said Tuesday.

Ukrainian President Volodymyr Zelenskyy this week accused North Korea of transferring personnel to Russia’s armed forces, saying his intelligence agencies had briefed him on “the actual involvement of North Korea in the war” in Ukraine.

The Kremlin has dismissed the allegation as “fake news.”

White House National Security…