There will be an emergency meeting of the UN Security Council today after North Korea fired a ballistic missile.
It's understood to have flown more almost 1,000 kilometers towards Japan before landing in the sea.
State television in North Korea - also known as the Democratic People's Republic of Korea (DPRK) - claimed the country's weapons "do not pose any threat to any country and region as long as the interests of the DPRK are not infringed upon".
South Korea's president Moon Jae-in says the action increases tensions on the Korean peninsula, and "gravely endangers international peace and security".
Pyongyang claims the missile is capable of 'striking the whole US mainland', and was "significantly more" powerful than previous missiles it had tested.
President Donald Trump, however, says this doesn't change America's approach to the secretive state:
