Update: This story originally said that a comprehensive arms trade embargo would close a loophole that has allowed North Korea to import “light arms, conventional weapons and ammunition,” as opposed to “small arms, light weapons, and ammunition.” We regret the error.

The U.S. presented a punishing new sanctions package to the UN Security Council on Thursday, responding to North Korea’s fourth nuclear test and February rocket launch, events which violated four sets of international sanctions.

With a Security Council vote on the measures assumed to take place this weekend, the new sanctions package – which has crucial Chinese backing – will represent the sharpest ever rise in