North Korea has fired two short-range ballistic missiles off its east coast, South Korea’s Joint Chiefs of Staff and national media said.

“The Joint Chiefs of Staff (JCS) said it detected the launches from the Tongchon area in Kangwon Province,” South Korea’s Yonhap News Agency reported on Friday.

South Korea’s military is “maintaining a full readiness posture in close cooperation with the United States”, the JCS said in a text message sent to reporters, according to Yonhap.

The Tongchon launch site is located some 60km (37 miles) from the inter-Korean border. The area was apparently closer to South Korean territory than any other launch location that North Korea has used so far this year.

The missiles, which were launched at 11:59am and 12:18pm local time on Friday (01:59 GMT and 02:18 GMT), flew an estimated 230km (140 miles) at a maximum altitude of 24km (15 miles) and reached top speeds of Mach 5, the JCS said.

“The North’s ballistic missile launches this time are acts of significant provocation that undermine peace and stability not only on the Korean Peninsula but also in the international community,” the chiefs said in a statement, according to Yonhap.

The launch on Friday also comes on the final day of South Korea’s annual 12-day “Hoguk” military exercises, which also involved an unspecified number of American troops this year.

Next week, South Korean and United States forces are also preparing to stage major combined air drills, named “Vigilant Storm”, Yonhap reported.

Such military drills infuriate Pyongyang, which sees them as rehearsals for an invasion and justifies its blitz of missile launches as necessary “countermeasures”.

Seoul and Washington have repeatedly warned that Pyongyang could be close to testing an atomic bomb for the first time since 2017, after a flurry of ballistic missile launches.

Leader Kim Jong Un has made developing tactical nukes — smaller, battlefield-ready weapons — a priority and Seoul recently warned North Korea could be preparing to conduct multiple consecutive nuclear tests as part of this drive.

On Tuesday, South Korean President Yoon Suk-yeol said North Korea was poised to conduct another nuclear test, which would be its seventh.

“It appears they have already completed preparations for a seventh nuclear test,” he told parliament on Tuesday during a budget speech.

On Wednesday, the US, South Korea and Japan warned that an “unparalleled” response would be warranted if North Korea tests a nuclear weapon.

The US Indo-Pacific Command said in a brief statement that the North’s missile launch was “unlawful” and that the US commitment to defending South Korea and Japan was “ironclad”.