TOKYO (AP) -- U.S. national security adviser John Bolton on Saturday called a series of short-range missile tests by North Korea earlier this month a violation of U.N. Security Council resolutions and said sanctions must be kept in place.
Washington's position on the North's denuclearization is consistent and a repeated pattern of failures to rid North Korea of nuclear weapons should be stopped, Bolton said, defending the recent U.S. seizure of a North Korean cargo ship. The U.S., however, is willing to resume talks with North Korea at any time, Bolton said.
Bolton was speaking to reporters in Tokyo ahead of President Donald Trump's arrival for a four-day visit to Japan.
North Korea tested short-range ballistic missiles on May 4 and 9, ending a pause in launches that began in late 2017. The tests are seen as a way of pressuring Washington to compromise without actually causing the negotiations to collapse.
"U.N. Security Council resolutions prohibit North Korea from firing any ballistic missiles," Bolton said. "In terms of violating U.N. Security Council resolutions, there is no doubt about that."
Trump and other officials have played down the significance of the missile tests.
During his visit, Trump and Japanese Prime Minister Shinzo Abe will "talk about making sure the integrity of the Security Council resolutions are maintained," Bolton said. The two leaders are also expected to discuss Iran, as well as trade and the bilateral security alliance, after playing golf and watching sumo wrestling Sunday.
Bolton's comments came a day after North Korea's official media said nuclear negotiations with Washington won't resume unless the US. abandons what Pyongyang describes as unilateral disarmament demands.
In a statement carried by the Korean Central News Agency, a North Korean spokesman accused the U.S. of deliberately causing February's collapse of talks between Trump and North Korean leader Kim Jong Un by making unilateral and impossible demands. The North has also strongly protested the recent U.S. seizure of a North Korean cargo ship that was involved in banned coal exports and demanded its immediate return.
Washington says the talks broke down because North Korea demanded sanctions relief in exchange for partially surrendering its nuclear capabilities.
Bolton brushed off the North Korean rhetoric, saying, "I take much of what they say with a grain of salt." Calling the U.S. seizure of the North Korean ship "appropriate," Bolton said it may be a good time to discuss the return of the USS Pueblo, a naval intelligence ship held by the North since 1968.
Bolton acknowledged the U.S. has not been "hearing much from North Korea" since February's Hanoi summit. The U.S. special envoy to North Korea, Stephen Biegun, "can't wait to talk to his North Korean counterpart, but they haven't responded," he said, adding that Biegun was "ready at any point to get on a plane and go anywhere."
Trump's visit will largely highlight close ties with Abe, who is now willing to hold a summit with Kim without preconditions — a recent change from his long-held hawkish stance. Abe had said previously he won't meet Kim unless the North takes concrete steps toward denuclearization and resolves a decades-long dispute involving Japanese nationals abducted by North Korea.
Bolton said he fully supports a possible Abe-Kim summit as an additional push toward resolving North Korea's missile and nuclear threats.
"Given Abe's willingness to hold this meeting with Kim Jong Un ... it would be certainly in North Korea's interest to accommodate the prime minister," he said.