Seoul's military said it had detected the launch Sunday of an intermediate-range ballistic missile -- Pyongyang's seventh weapons test in January.

North Korea has never test-fired this many missiles in a calendar month before and last week threatened to abandon a nearly five-year-long self-imposed moratorium on testing long-range and nuclear weapons, blaming US "hostile" policy for forcing its hand.

"The evaluation test-fire of Hwasong 12-type ground-to-ground intermediate- and long-range ballistic missile was conducted Sunday," the official Korean Central News Agency said.

The test "confirmed the accuracy, security and effectiveness of the operation of the Hwasong 12-type weapon system under production," KCNA added.

KCNA said the test was carried out using the "highest-angle launch system" to ensure the safety of neighboring countries, and that the warhead carried a camera that took photos while it was in space.

With peace talks with Washington stalled, North Korea has doubled down on leader Kim Jong Un's vow to modernise the regime's armed forces, flexing Pyongyang's military muscles despite biting international sanctions.

South Korea said Sunday that North Korea appeared to be following a "similar pattern" to 2017 -- when tensions were last at breaking point on the peninsula -- warning Pyongyang could soon restart nuclear and intercontinental missile tests.

The last time Pyongyang tested an intermediate-range missile was the Hwasong-12 in 2017, which analysts said at the time was powerful enough to put the US territory of Guam in range.

The string of launches in 2022 comes at a delicate time in the region, with Kim's sole major ally China set to host the Winter Olympics next month and South Korea gearing up for a presidential election in March.