This article discusses how relations of both the U.S. and China with DPRK are changing. China has finally followed through with coal sanctions. At the same time, there is talk of some North Korean diplomats coming to the U.S. to meet with former officials. Although this would not be officially contact, it is definitely a change in previous policy with DPRK.
When DPRK conducted more missile tests a few weeks ago, Donald Trump received criticism for not having a solid policy on what to do about North Korea. For the most part, just ignoring DPRK and not giving attention but still showing the strength of the U.S. has seemed to work in the past. However, as Donald Trump is changing a lot of policies and precedents, it will be interesting to see if he changes policy on North Korea. Hopefully China will not take advantage of his lack of policy to pressure the U.S. into changing relations with North Korea.