The United States said on Wednesday it would seek new sanctions on North Korea at the United Nations after it fired a volley of missiles, including possibly its largest intercontinental ballistic missile, AFP reported.
The latest launch came just hours after US President Joe Biden left Asia on Tuesday.
Three missiles, including one ICBM, were fired in the latest launch from the Sunan area in Pyongyang, South Korea said.
North Korea has conducted more than a dozen weapons tests since January, including the firing an intercontinental ballistic missile at full range for the first time since 2017.
Washington plans to call for a UN Security Council vote on tougher sanctions on Pyongyang after the tests, a senior US official said on Wednesday, according to AFP.
The official expected a vote "in the coming days" and noted that a previous Security Council resolution called for further consequences in the event of a further ICBM launch.
"That was a provision of that resolution. That's precisely what happened and so we feel it's now time to take action," the official said on condition of anonymity.
The three early-morning ballistic missile launches came within an hour of each other, South Korea's Joint Chiefs of Staff said in a statement on Wednesday.
"The first ballistic missile (suspected ICBM) had a range of around 360 kilometers (225 miles) and an altitude of around 540km," Seoul's Joint Chiefs of Staff said in a statement.
This could have been North Korea's largest ICBM, the Hwasong-17, Kim Tae-hyo said later.
The second ballistic missile "disappeared at an altitude of 20km" and the third -- a suspected short-range ballistic missile -- travelled around 760km at an altitude of around 60km.
North Korea has ramped up its missile tests ever since talks with Washington on denuclearization failed.
Former US President Donald Trump tried to reach an agreement with North Korea while in office. Kim and Trump met in Hanoi in 2019 for a summit that left nuclear talks at a standstill.
The pair had met three times since June 2018 but made little progress towards denuclearization.
The Biden administration reached out to North Korea shortly after taking office, but the country did not respond to those overtures.
The Biden administration says it is ready to start talks with North Korea without preconditions, but would pursue working-level negotiations and not the pageantry of another summit.