North Korea said on Thursday that it launched a "newly developed new-type tactical guided projectile", Reuters reported, citing state news agency KCNA.
The report suggested North Korean leader Kim Jong Un did not inspect the launch.
The new weapon is based on existing technology that was improved to carry a 2.5-ton warhead, KCNA reported.
The pair of test-fired weapons accurately hit a target 600 km away, said the North Korean news agency.
Photos released by state media showed a black-and-white painted missile blasting off from a military launch vehicle.
On Wednesday night, officials in South Korea, Japan and the US said that North Korea fired at least one unidentified projectile into the sea.
It marked North Korea's second missile launch in recent days. Previously, it launched two projectiles in its first missile test since US President Joe Biden took office.
Former US President Donald Trump tried to reached an agreement with North Korea while in office. Kim and Trump met in Hanoi in 2019 for a summit that left nuclear talks at a standstill.
The pair had met three times since June 2018 but made little progress towards denuclearization.
The new Biden administration reached out to North Korea but the country did not respond to those overtures.
Top North Korean diplomat Choe Son Hui confirmed last week that the United States had recently tried to initiate contact with Pyongyang, but blasted the attempts as a “cheap trick” that would never be answered until Washington drops hostile policies.
Biden said on Thursday the United States remains open to diplomacy with North Korea despite its latest missile tests, but also warned there would be responses if North Korea escalates matters.