Nikki Haley, the U.S. ambassador to the United Nations, claimed the measures - which are a watered-down version of the original US-drafted plan - will starve North Korea of at least $1.3bn in annual revenues. It also bans imports of textiles from North Korea, stripping the country of another key source of hard currency.
"I believe what President Trump wanted to say was that, not only South Korea and the USA, but also China and Russian Federation all together need to respond very firmly against North Korea's nuclear provocations", he said.
Analysts for 38 North, who are devoted to reporting on the regime, believe this activity may indicate that preparation for future tests in other underground portals is underway.
"You can see that the explosion visibly displaces the mountain, which demonstrates both how large the explosion was but also that it occurred in the same tunnel complex as the preceding four nuclear tests", said Lewis on the Arms Control Wonk website. That would be much higher than most official estimates, which have varied.
In a statement issued by North Korea's official news agency, Pyongyang said it would use nuclear weapons to "sink" Japan and "reduce the U.S. mainland to ashes and darkness". Satellite imagery since the test has showed evidence of numerous landslides at the test site.
"If the claim that the device just tested has a variable yield is true (from tens to hundreds of kilotons), then this may also imply the North Koreans intend to adopt an expanded policy of using nuclear weapons, including tactical use, in addition to deterring threats to existence of the state", 38 North said. She added that the images from the North's nuclear test in 2016 did not show substantial change on the mountain's surface. "No way... A use of military force, but that would result in a second Korean war".
Secretary of State Rex Tillerson held talks in London with senior British and French officials on North Korea's nuclear and missile programs.
South Korea's military said the Taurus missile fired from an F-15 fighter jet traveled through obstacles at low altitudes before hitting a target off the country's western coast during drills Tuesday.
Before he took over in January as President Donald Trump's Pentagon chief, Mattis had suggested that the silo-based, long-range weapons, known as intercontinental ballistic missiles, might be expendable.