The United States and South Korea will maintain the "strongest possible joint deterrent" over North Korea's "escalatory actions", the US envoy on North Korea said on Monday, according to Reuters.
US Special Representative Sung Kim and his deputy, Jung Pak, met South Korean officials, including nuclear envoy Noh Kyu-duk, after arriving in Seoul early on Monday for a five-day visit.
"It is extremely important for the United Nations Security Council to send a clear signal to the DPRK that we will not accept its escalatory tests as normal," Kim was quoted as having told reporters after his talks with Noh, referring to North Korea by its official name, the Democratic People's Republic of Korea.
"We agreed on the need to maintain the strongest possible joint deterrent capability on the peninsula," he said.
Kim added the allies would "respond responsibly and decisively to provocative behavior," while underlining his willingness to engage with North Korea "anywhere without any conditions."
The statements came a day after North Korean media reported that leader Kim Jong Un supervised the test-firing of a new guided weapons system to improve the country’s "tactical nukes".
The launch was the latest in an unprecedented blitz of sanctions-busting weapons-tests this year, which included firing an intercontinental ballistic missile at full range for the first time since 2017.
The US envoy said at the start of April that the United States plans to introduce a new resolution in the UN Security Council in response to North Korea's recent ballistic missile tests.
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.
In Biden’s first policy speech to Congress, he said nuclear programs in North Korea and Iran posed threats that would be addressed through “diplomacy and stern deterrence”.
Responding to that speech, North Korea dismissed the idea of talks with Washington, saying Biden’s speech was “intolerable” and “a big blunder."