U.S. Undersecretary of State John Bolton on Thursday welcomed Japan's passage of legislation last week aimed at imposing economic sanctions on North Korea.

"Judiciously applied sanctions can have a very important impact in the round of nonproliferation," Bolton told a news conference at the U.S. Embassy in Tokyo. The legislation is a "positive step" toward international nonproliferation efforts, he said.

Last week, the Diet passed a revised bill allowing the government to ban cash remittances and trade to North Korea, and lawmakers of the Liberal Democratic Party are currently preparing a separate bill that will allow Japan to ban North Korean ships from entering its ports.

Bolton criticized North Korea for abducting Japanese nationals to the North in the 1970s and 1980s, calling it an "act of terrorism."

He maintained that the United States will "firmly" support Japan's position in dealing with the abduction issue.