Delegates to the UN Security Council have seen authorities in North Korea carry out repeated missile launches, despite their calls to defuse tensions. They have blamed some envoys of "inaction."

Members gathered Monday to address the launch on Thursday of what the North Koreans say is a new type of intercontinental ballistic missile, the Hwasong-18.

US Ambassador Linda Thomas-Greenfield said the Council must do everything in its power to prevent the North from carrying out future unlawful launches or a seventh nuclear test. She said "two members" continue to defend North Korea. Delegates from China and Russia have used their veto power to block a resolution to impose tougher sanctions.

Japanese Ambassador Ishikane Kimihiro said the council's refusal to enforce its own resolutions has undermined its credibility.

Chinese Ambassador Zhang Jun said US military exercises around the Korean Peninsula are the "main trigger" for the tensions. Russian Ambassador Vassily Nebenzia accused the Americans of "churning out" Security Council meetings for "purely propaganda purposes."

An official with North Korea's ruling Workers' Party added to the criticism. Ri Pyong Chol issued a statement saying the development of new weapons is a "legitimate measure" for bolstering self-defense.