North Korea said Saturday its missile tests are for self-defense in response to U.S. military threats and do not pose a danger to air traffic or neighboring countries.

The statement by a spokesman for the country's National Aviation Administration came after North Korea on Thursday conducted its sixth round of ballistic missile launches since late September, following one that flew over Japan for the first time since 2017.

The missile testing is "regular and planned self-defensive step for defending the country's security and the regional peace from the U.S. direct military threats that have lasted for more than half a century," the state-run Korean Central News Agency quoted the unnamed spokesman as saying.

He said the tests do not "pose any threat and harm to the safety of not only civil aviation but also the neighboring countries and region," according to KCNA.

The statement was released after the International Civil Aviation Organization recently condemned North Korea's continued ballistic missile launches over or near international air routes.

The spokesman said Pyongyang "categorically condemns and rejects" the ICAO move "as a political provocation of the U.S. and its vassal forces aimed to infringe upon the sovereignty" of North Korea.

In a separate statement, a spokesman for North Korea's Defense Ministry slammed the involvement of the U.S. nuclear-powered aircraft carrier Ronald Reagan in a naval exercise with South Korea in the Sea of Japan through Saturday.

Criticizing the U.S. warship's presence as "an event of considerably huge negative splash to the regional situation," the unnamed spokesman said in response to a question from KCNA that North Korea's armed forces are "seriously approaching the extremely worrisome development of the present situation."

He said the ballistic missile launch over the Japanese archipelago on Tuesday was a "righteous reaction" to "extremely provocative and threatening" U.S.-South Korea military drills involving the aircraft carrier in late September.

The redeployment of the carrier to waters off the Korean Peninsula was "a sort of military bluffing," he said.

The Ronald Reagan participated in joint drills with South Korea's navy from Sept. 26 to 29, before joining the first anti-submarine exercise in five years in the Sea of Japan held by the two countries and Japan on Sept. 30.

It returned to the waters for further exercises shortly after Tuesday's missile firing that covered the longest distance ever for a launch by Pyongyang. The carrier's home port is Yokosuka, near Tokyo.

Since the start of the year, North Korea has conducted more than 20 rounds of ballistic missile tests in violation of U.N. Security Council resolutions.

There is growing concern that North Korea may conduct its seventh nuclear test and first since September 2017 in the near future.

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