(AP) -- Trump said on Twitter on Sunday the United States is considering halting trade with "any country doing business with North Korea." His remarks came after North Korea detonated a thermonuclear device in its sixth and most powerful nuclear test.

Geng Shuang, a Chinese Foreign Ministry spokesman, told reporters at a briefing in Beijing on Monday that China regarded as "unacceptable a situation in which on the one hand we work to resolve this issue peacefully but on the other hand our own interests are subject to sanctions and jeopardized."

Geng said: "This is neither objective nor fair."

China is the North's closest ally and commercial partner.

(Photo: Getty)