I found this.
China is North Korea’s biggest trading partner by some margin.
That means the trading amount is nearly 0?
North Korea's Top Trading Partners:
China: US$1.7 billion (90.8% of total North Korean exports)
Pakistan: $29.2 million (1.6%)
India: $26.1 million (1.4%)
France: $12.4 million (0.7%)
large amount or number of something:
It'll be some time before we meet again.
We discussed the problem at some length.