Even China is putting the squeeze on its unpredictable client state:
Now that China has completely joined the international effort to ban weapons exports to North Korea the nuclear weapons program in the north will be delayed, at the very least. The Chinese ban means many industrial items North Korea needs to make a workable nuclear warhead are no longer easily available from Chinese manufacturers. This is critical because North Koreans have not yet “weaponized” their nuclear device design to work in a missile (or even an aircraft bomb). Russia had earlier made it very difficult for North Korea to obtain Russian warhead tech. In the past Russia has allowed older ballistic missile tech to be sold to North Korea, but is not allowing any nuclear warhead stuff out. The same with technical assistance from Pakistan, which was helped by China to develop its nuclear warhead equipped missiles. The Chinese have apparently persuaded the Pakistanis to rebuff North Korean offers to buy warhead tech.
It’s good to see Beijing act like such grownups, especially since the region probably can no longer count on the same thing from Washington.