US diplomats have asked the United Nations Security Council to impose stronger sanctions on North Korea for its missile launches. But, on Thursday, the Chinese and the Russians blocked their efforts.

Security analysts had warned the North Koreans could carry out a nuclear or missile test during US President Joe Biden's visit to South Korea and Japan.

Authorities fired three missiles toward the Sea of Japan on Wednesday, including one believed to be an intercontinental ballistic missile. The launches came just after Biden had left Tokyo.

US delegates drafted a resolution to cut supplies of crude oil and petroleum to North Korea, and they wanted to freeze the assets of North Korean hackers. UN officials believe the country raises money through cyberattacks to fund their weapons programs.

The Russian ambassador described the use of sanctions as "primitive." The Chinese ambassador criticized the Americans for failing to address issues through dialogue.

The envoys from Japan and South Korea said the vetoes left them with "deep regret."

US and Japanese officials said they're strengthening their capabilities "to deter and counter regional threats." After the launch, their fighter jets flew together over the Sea of Japan.

The US and South Korean militaries carried out missile tests.