North Korean Vice Defence Minister Ryo Chol-ung has departed for Vietnam, according to state media, though no details were given about the delegation's itinerary or the purpose of the visit. The trip follows a sustained warming of relations between Pyongyang and Hanoi, which has included a landmark October summit between Kim Jong-un and Vietnamese President To Lam — the first visit by a senior Vietnamese leader to North Korea in 18 years — as well as subsequent exchanges between the two countries' foreign and security ministers. Kim Jong-un also sent a letter to President To Lam earlier this month reaffirming his commitment to strengthening ties, signalling that military-to-military engagement is now a growing part of the two nations' expanding partnership.