US Secretary of State Mike Pompeo, Japanese Foreign Minister Taro Kono and his South Korean counterpart Kang Kyung-wha on Sunday urged North Korea to take concrete steps toward complete denuclearization. The allied countries agreed to keep UN-backed economic sanctions on Pyongyang until it completely dismantles its nuclear program, DW reported.

US Secretary of State Mike Pompeo said that North Korea sanctions will not be lifted yet.

"We were able to reaffirm our unwavering commitment to the continued strengthening of our trilateral cooperation towards the common goal of North Korea's complete, verifiable and irreversible dismantlement of all nuclear weapons and missiles," Kono told a joint news conference in Tokyo.

The talks come a day after Pompeo's Pyongyang visit, which he dubbed successful. But on Saturday, North Korean officials rejected US demands for denuclearization, calling them "unilateral."

"The US is fatally mistaken if it went to the extent of regarding that the DPRK (North Korea's official name) would be compelled to accept, out of its patience, demands reflecting its gangster-like mindset," according to a statement relayed by the state-run KCNA news agency.