China
China was wary of both the US and Russia. 596 was first tested in 1964. It was meant as a deterrent to both the United States and Soviet Union. It then tested a hydrogen bomb in “Test No. 6” in 1967.
It is a signatory of the NPT, though it never ratified it.
The country, however, has a strict “no first-use” policy, meaning it provides an unqualified negative security assurance that it would only use the weapon when an enemy strikes them with the bomb first.