Photos of missile test-launches have been released by North Korea (Picture: KCNA).
The South Korean military says Pyongyang has fired at least one projectile off North Korea's eastern coast.
It comes just hours after the North announced nuclear negotiations with the US could resume this weekend.
South Korea says one missile may have been launched by a submarine, after being fired from the waters of the North's eastern coast, off the port of Wonsan.
Defence officials say that one projectile travelled 280 miles and reached an altitude of 565 miles, before reportedly landing in Japanese waters.
The news comes shortly after North Korean First Vice Foreign Minister Choe Son Hui announced preliminary contact with the US would be followed by "working-level" negotiations on Saturday to discuss North Korea's nuclear capability.
Kim Jong Un has supervised some of the several missile test-launches since the failure to reach an agreement with Mr Trump.