North Korea has fired a short-range missile towards the sea off its east coast early on Tuesday, said South Korea's military.
The test happened as North Korea's ambassador said at the UN that no-one could deny Pyongyang's right to self-defence and to test weapons.
Earlier this month Pyongyang test-fired both ballistic and cruise missiles.
But several days ago North Korea had also expressed willingness to engage in talks with the South.
The US military said in a statement on Tuesday that it was aware of the missile launch but that it posed no immediate threat to US personnel or its allies.
However, the US Indo-Pacific Command said that the launch "highlighted the destabilising impact of
illicit weapons program".On Tuesday, Japanese media quoted the defence ministry as saying that the projectile may have been a ballistic missile, which is banned under United Nations sanctions.
South Korean President Moon Jae-in has ordered Seoul's National Security Council to analyse any intentions behind Pyongyang's latest missile launch and recent statements from Kim Jong-un's powerful sister, Kim Yo-jong.
Kim had days earlier said they were open to Moon's proposal to formally declare an end to the Korean War, but added that the South needed to stop its "hostile policies" first.
