North Korea fires more than 10 missiles, Seoul says

North Korea fired more than 10 short-range ballistic missiles from the Pyongyang area on Thursday, South Korea's military said, hours after US President Donald Trump said he planned to meet North Korean leader Kim Jong Un this year.

South Korea's Joint Chiefs of Staff said the missiles were fired towards the East Sea at around 5:00 pm and flew about 300 kilometres. South Korean and US authorities were analysing their specifications.

South Korea's presidential office held an emergency security meeting after the launches, condemned them as a violation of UN Security Council resolutions and ordered heightened readiness.

The launches came as South Korea and the United States held a shortened edition of their annual Ulchi Freedom Shield military exercises. Seoul said the drills would end Friday, about a week earlier than planned, at the suggestion of the US side. The Pentagon said the reduction would cause “no degradation to US training objectives”.

Kim Yo Jong, the sister of Kim Jong Un, said Thursday that Trump's decision to scale back the drills was Seoul's “comeuppance”. She accused South Korea of having a “master-and-servant” relationship with the United States and said Seoul had “reaped what it sowed”.

She also criticised South Korean President Lee Jae Myung's remarks that he would support Trump's peacemaking efforts with North Korea, calling them “double-dealing”.

Trump told reporters at the White House on Wednesday that he planned to meet Kim later this year. He also said North Korea had 57 “very powerful” nuclear weapons. Seoul says North Korea has around 80 to 120.

Kim Yo Jong said Wednesday that her brother had “good memories and feelings” about Trump and that the relationship between the two leaders remained “excellent”. She said, however, that she was unaware of any current communication between them.

North Korea has long condemned US-South Korean joint exercises as rehearsals for invasion and often stages missile launches around the drills. The United States stations about 28,500 troops in South Korea, a deployment linked to the 1950-53 Korean War, which ended with an armistice rather than a peace treaty.