On the 2 March 2016 the UN Security Council adopted Resolution 2270, Non-proliferation/Democratic People’s Republic of Korea. This contains a number of port state and flag state obligations, of particular note see paragraphs 18, 22, and, 19, 20, 29-31, respectively. Media reports suggest China has already barred a North Korean vessel’s entry to the port of Rizhao.
The UNSC Resolution can be found here.
De Maribus 