US 'incredibly' concerned by Vladimir Putin threat to send North Korea weapons

"It is incredibly concerning," State Department spokesman Matthew Miller told reporters, following Putin's remarks in Vietnam.

The United States expressed deep concern Thursday over Russian President Vladimir Putin's threat to supply North Korea with weapons, warning such a move could destabilize the Korean peninsula.

North Korea's leader Kim Jong Un (R) and Russia's President Vladimir Putin (L) shaking hands after a signing ceremony (AFP)

"It is incredibly concerning," State Department spokesman Matthew Miller told reporters, following Putin's remarks in Vietnam that he "does not rule out" shipments to Pyongyang.

“It would destabilize the Korean peninsula, potentially, depending on the type of weapons, and might violate UN Security Council resolutions that Russia itself has supported.”