President Trump on Saturday brushed off concerns about recent North Korean missile tests during his trip to Japan.

"North Korea fired off some small weapons, which disturbed some of my people, but not me," he posted on Twitter. "I have confidence that Chairman Kim will keep his promise to me"

The tweet contradicts a statement by his national security advisor John Bolton, who called North Korea's tests "extremely regrettable."

Trump published the tweet as he was meeting Japanese president Shinzo Abe this weekend to discuss trade between the two nations.

Trump's statement about North Korea leader Kim Jong-un could unnerve the Japanese, as Japan is threatened by missile tests done by nearby North Korea.

Trump had tweeted that "great progress" was made on trade negotiations between Japan and the U.S., despite his comments about Kim.  

The Trump administration is hoping that diplomatic talks can continue between Washington and Pyongyang, in hopes that North Korea would be able to support a denuclearization deal. A previous attempt in February between Trump and Kim in Vietnam failed to result in any concrete agreement between the two countries.