South Korea on June 21 summoned the Russian ambassador, Georgy Zinoviev, to lodge a strong protest after Russian President Vladimir Putin and North Korea’s supreme leader, Kim Jong Un, signed a mutual defence pact on June 19 in Pyongyang. South Korea’s First Vice Minister Kim Hong-kyun relayed Seoul’s “stern position” on Kim and Putin’s defence pact and urged Moscow to “immediately halt military cooperation.” Meanwhile, Putin warned South Korea that it would be making “a big mistake” if it armed Ukraine in the war against Russia.