Japan, the United States and South Korea have agreed that North Korea should take action on denuclearization before the six-party talks on its nuclear threat can resume, a senior Japanese official said.

North Korea "must use not only words but also actions to demonstrate that it is going in the direction of denuclearization," Shinsuke Sugiyama said after meeting in Washington on Wednesday with his U.S. and South Korean counterparts.

The senior officials discussed the actions that the three countries will ask Pyongyang to take, according to Sugiyama, who heads the Asian and Oceanian Affairs Bureau at the Foreign Ministry.

Cho Tae Yong, who represented South Korea at the trilateral meeting and is Seoul's chief envoy to the stalled six-party talks, told reporters that "stronger requirements should be imposed" on North Korea than a February 2012 U.S.-North Korea deal, the South's Yonhap News Agency reported.

Under the deal, Pyongyang agreed to shut down uranium enrichment and other activities at its Yongbyon nuclear complex and refrain from conducting new nuclear and long-range missile tests. But the deal quickly fell apart after North Korea launched a long-range missile in April 2012.

Sugiyama said they also reaffirmed the importance of trilateral cooperation in response to North Korea's proposal for bilateral talks with the United States.