The missile dubbed "Pulhwasal-3-31" is currently under development and the test-firing had no impact on the security of neighboring countries, the state media said, adding it had "nothing" to do with the regional situation.
The test was also part of the process of updating the country's weapon system, the report said.
South Korea's Joint Chiefs of Staff said on Wednesday that the North had fired multiple cruise missiles towards the sea off its west coast while Seoul's defense minister, Shin Won-sik, condemned the launches as a serious threat to his country.
North Korea, which has tested dozens of missiles in the last year including its first intercontinental ballistic missiles since 2017, has upped the rhetoric in recent weeks.
Earlier this month, the country launched a hypersonic missile. In response, South Korea, the United States and Japan carried out joint naval drills in waters off southern Jeju Island.
North Korea then announced it had tested an "underwater nuclear weapon system" in response to the joint naval exercises.
North Korean leader Kim Jong Un said in late December that Pyongyang would not hesitate to respond with a nuclear attack when an enemy provokes it with nuclear weapons.
Days later, Kim told the country's military commanders that the most powerful means must be mobilized to destroy the United States and South Korea if they choose a military confrontation.
