North Korea fired two suspected cruise missiles into the sea off its east coast early on Tuesday, South Korean officials said, according to Yonhap news agency.
South Korea's military is assessing the launches to determine the nature of the projectiles. Cruise missiles are not banned under the United Nations sanctions imposed on Pyongyang, unlike ballistic missiles.
A military official told the Associated Press that the tests were conducted from an inland area, but did not specify the exact location.
Pyongyang has recently conducted four rounds of ballistic missile tests. The last one was conducted on January 17.
North Korea has increased testing activities recently, in what experts believe is provocation to US President Joe Biden's administration over stalled diplomacy. The isolated nation's economy has suffered heavily due to the pandemic and economic sanctions.
Why has North Korea increased test launches?
Last week, North Korea hinted that it could resume the testing of nuclear explosives and long-range missiles targeting mainland USA.
"Cruise missiles are slower than ballistic missiles and so are regarded as less of a threat, but they hit targets with high precision, something North Korea would continue to develop," Lee Sang-min, a military expert at the Korea Institute for Defense Analyses told Reuters.
North Korea's recent tests are the biggest cluster since 2019. They have invoked concern from UN Secretary General Antonio Guterres, and have also prompted more sanctions from the US.
Diplomatic talks between Pyongyang, and Seoul and Washington have come to a standstill. Biden has expressed willingness to continue open-ended relations only if North Korea controlled its missile tests and abandoned its nuclear weapons.
Kim has also expressed willingness to continue talks, if the US drops "hostile policies" such as sanctions and military drills.
China and Russia have pushed the UN Security Council to remove a ban on Pyongyang's exports of statues, seafood and textiles.