North Korea's foreign minister said on Tuesday that whether it conducted another nuclear test depended on the behavior of the United States, South Korea's Yonhap news agency reported.
The minister, Ri Yong Ho, said, however, that the United States had destroyed the possibility of a nuclear-free Korean peninsula.
North Korea conducted its fourth nuclear test in January, triggering tough new international sanctions. South Korean officials and experts believe it can conduct a fifth test at any time.
"Any additional nuclear test depends on the position of the United States," Yonhap quoted Ri as telling reporters on the sidelines of a meeting of the Association of South East Asian Nations (ASEAN) in Laos.
Ri added that North Korea was a responsible nuclear state and repeated its position that it would not use atomic arms unless threatened.