North Korea's latest nuclear test was met with strong rhetoric from the White House — and that's left China in a tough spot.
President Donald Trump recently tweeted the U.S. might end trade with countries that do business with North Korea.
That prompted a response from China, North Korea's primary trading partner and only major ally. A spokesman for China's foreign ministry said the move would be "unacceptable" and "unfair."
But China's options are limited: The idea of a unified, democratic Korea allied with the U.S. isn't an attractive option, and neither is the thought of war on the Korean peninsula. Additionally, political upheaval in the North could result in a wave of refugees coming into China.
The U.S. has taken China to task for its support of North Korea, even though the two nations have at times worked together to try and get Kim Jong-un's regime to denuclearize.
The U.S. previously sanctioned six Chinese companies accused of supporting North Korea's weapons program. But an all-out trade ban would wipe out the billions of dollars' worth of trade between the U.S. and China each month.
Trump's trade policies have taken aim at another ally against North Korea's aggressions.
Around the time the North announced its sixth and most powerful nuclear test — which it claims was a thermonuclear weapon, aka a hydrogen bomb — reports surfaced that Trump was mulling whether or not to withdraw from the free trade agreement with South Korea.
The president could announce his plans on the South Korea free trade deal as early as this week.
Similarly, Treasury Secretary Steven Mnuchin said he was going to write up harsher sanctions that would "cut off North Korea economically." Mnuchin said the administration would work with other countries, including China, but the sanctions he's drafting would prevent anyone "doing trade or business" with North Korea from engaging with the U.S.