North Korea hosted a high-profile event at a luxury European hotel in Beijing last week to mark the anniversary of its mutual defense treaty with China — a rare and conspicuous move that experts say signals a renewed strategic alignment between the two countries and likely breaches U.N. sanctions.

The event, marking the 64th anniversary of the signing of the Treaty on Friendship, Cooperation and Mutual Assistance between China and the DPRK took place at the flagship Beijing Yansha Center location of Kempinski Hotels S.A., a Geneva, Switzerland-based luxury hotel chain. The property boasts 480 rooms and suites as well