SEOUL, South Korea -- North Korea fired several projectiles believed to be short-range surface-to-ship cruise missiles off its east coast Thursday, South Korea's military said, a continuation of weapons tests that have rattled Washington and the North's neighbors as Pyongyang seeks to build a nuclear missile capable of reaching the continental United States.

South Korea's Joint Chiefs of Staff said in a statement that the launch came from the North Korean eastern coastal town of Wonsan, and that the projectiles likely flew about 125 miles. The statement said the launches were immediately reported to South Korean President Moon Jae-in but gave no further details.

The North's missile tests present a difficult challenge to Moon, a liberal elected last month who has expressed a desire to reach out to Pyongyang. North Korea, which could have a working nuclear-tipped ICBM in the next several years, may also be the most urgent foreign policy concern for the Trump administration, which has been distracted by domestic political turmoil.

With each test by North Korea of missiles, the U.N. Security Council expresses more frustration that its condemnations and assets freezes are doing little to halt the advancement of Pyongyang's nuclear program, CBS News' Pamela Falk reports from the U.N. Cruise missiles are not subject to the U.N. sanctions.

All five permanent members of the Security Council have said that no major new sanctions will be imposed as a result of the continuous testing of missiles; a Security Council diplomat said today that it would take a nuclear test to up the ante on sanctions, and even then, China might be reluctant to squeeze North Korea too hard, Falk adds. 

After the Council vote on June 3, adopting a new resolution that expanded existing sanctions to 14 individuals and four entities, U.S. Ambassador Nikki Haley said the "Security Council is sending a clear message to North Korea today -- stop firing ballistic missiles or face the consequences."

Last week, North Korea fired a short-range ballistic missile that landed in Japan's maritime economic zone, prompting protest from both Tokyo and Seoul.

North Korea's weapons tests are meant to build a nuclear and missile program that can stand up to what it sees as U.S. and South Korean hostility, but they are also considered by outside analysts as ways to make its political demands clear to leaders in Washington and Seoul. These demands include the removal of nearly 30,000 U.S. troops in South Korea meant to check North Korean aggression.

The launches from Wonsan were North Korea's fourth test in as many weeks as the country continues to speed up its development of nuclear weapons and missiles.

North Korea on May 14 premiered a powerful new midrange missile that it said could carry a heavy nuclear warhead. Experts said that rocket flew higher and for a longer time than any other missile previously tested by North Korea, and that it could one day reach targets as far away as Hawaii and Alaska.

The North in following weeks launched a solid-fuel midrange missile that can be fired on shorter notice than liquid fuel missiles, and also what it descried a new "precision-guided" missile, which experts say is designed with a maneuverable terminal stage meant to frustrate missile defense systems like the U.S. Terminal High Altitude Area Defense that is being deployed in South Korea.

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