North Korea's missile launches could be the groundwork for a return to intercontinental ballistic missile and nuclear bomb tests this year for the first time since 2017, the U.S. Directorate of National Intelligence (DNI) said in its annual Worldwide Threat Assessment released on Monday.
On Tuesday, U.S.-based analysts said commercial satellite imagery shows construction at North Korea's nuclear testing site for the first time since it was closed in 2018.
International experts have also reported that North Korea's main nuclear reactor facility at Yongbyon appears to be in full swing, potentially creating additional fuel for nuclear weapons.
The DNI report, dated Feb. 7, and released ahead of a congressional hearing on Tuesday, said North Korean leader Kim Jong Un remained strongly committed to expanding his nuclear weapons arsenal and ballistic missile research and development.
It said North Korea's continued development of ICBMs, intermediate-range ballistic missiles and submarine-launched ballistic missiles showed the country's intention to bolster its nuclear delivery capability.
"In January, North Korea began laying the groundwork for an increase in tensions that could include ICBM or possibly a nuclear test this year - actions that Pyongyang has not taken since 2017," the report said.
"Flight tests are part of North Korea's effort to expand the number and type of missile systems capable of delivering nuclear warheads to the entire United States," it added.
The DNI report said it based its assessment on information available as of Jan. 21.
A return by North Korea to ICBM or nuclear testing would be a massive additional headache for the administration of U.S. President Joe Biden, even as he grapples with the crisis caused by Russia's invasion of Ukraine.
Amid stalled denuclearization talks, North Korea has suggested it could resume testing nuclear weapons or ICBMs.
It tested a record number of missiles in January, including its largest since 2017, and appears to be preparing to launch a spy satellite.
The United States and 10 other countries on Monday bemoaned the failure of the United Nations Security Council to condemn North Korea's missile launches this year, saying this eroded the credibility both of the council and the global non- proliferation regime.