Even before North Korea detonated its most powerful nuclear bomb yet, Japan was calling for moves to cut off its oil supply.
Afterward, U.S. President Donald Trump threatened to halt all trade with any country that does business with Kim Jong Un's regime. China, which supplies most of its food and fuel, on Monday called the warning "unacceptable."
Some sort of oil embargo is likely to come up as the international community discusses a response to the nuclear test, with the United Nations Security Council meeting overnight. China has resisted such a move in the past over fears that North Korea might collapse, but has grown increasingly frustrated with its rogue ally.