North Korea fired an intermediate-range ballistic missile on Sunday, the second in a week.
The launch verified the reliability and accuracy of the solid-fuel engine's operation and stage separation and the late-stage guidance of the nuclear warhead.
Local media report the nation's leader Kim Jong Un saying with pride that the missile's hit rate is very accurate. He has now approved the weapon's deployment for action.
"Viewing the images of the Earth being sent real-time from the camera mounted on the ballistic missile, Supreme leader Kim Jong Un said it feels grand to look at the Earth from the rocket we launched, and the entire world looks so beautiful," local media KCNA reports.
The missile flew about 500 kilometers (310 miles) and reached an altitude of 560 kilometers (350 miles). It landed in waters off North Korea's east coast.
Reuters reports that North Korea announced on Saturday that it had developed the capability to strike the U.S. mainland, although Western missile experts say the claim is exaggerated.
"For military purposes, solid-fueled missiles have the advantage that they have the fuel loaded in them and can be launched quickly after they are moved to a launch site," David Wright, co-director of the Global Security Program at the U.S.-based Union of Concerned Scientists, said in a blog post.
However, building large solid missiles is difficult, Wright said. It took decades for major superpowers such as France and China to go from a medium-range missile to an intercontinental ballistic missile. "So this is not something that will happen soon, but with time North Korea will be able to do it," Wright said.
If it did happen, the U.S. President would have about 10 minutes to decide whether or not to launch a retaliatory attack. A missile launched from North Korea could hit the U.S. within 30 minutes.
An official traveling with U.S. President Donald Trump in Saudi Arabia said that the missile had a shorter range than the three previous missiles that North Korea had tested. Reuters reports U.S. Secretary of State Rex Tillerson saying economic and diplomatic pressure would continue to be applied to North Korea.