North Korea launched several unidentified projectiles into the sea yesterday, the South Korean military said, in what could be Pyongyang's first short-range missile launch for more than a year as it seeks to up pressure on Washington with nuclear talks deadlocked.

The US and North Korea have been at loggerheads since the collapse of a summit between Kim Jong Un and Donald Trump in February, when the two sides clashed over sanctions and the extent of Pyongyang's concessions on its atomic arsenal.

North Korea "fired a number of short-range projectiles" from Hodo peninsula near the east coast town of Wonsan in a northeast direction from 9:06 am (0006 GMT) to 09:27 am, the South's Joint Chiefs of Staff said in a statement.

The projectiles travelled from 70 to 200 kilometres (45 to 125 miles) towards the East Sea, also known as the Sea of Japan, the JCS added.

In an earlier statement, it had said

Pyongyang had launched an unidentified short-range missile. The last North Korean missile launch was in November 2017.

The latest firing comes just a day after South Korean Foreign Minister Kang Kyung-wha said Pyongyang should show "visible, concrete and substantial" denuclearisation action if it wants sanctions relief.

That issue was also at the centre of the February talks in Hanoi, where North Korea demanded immediate sanctions relief, but the two sides disagreed on what Pyongyang should give up in return.

Earlier this week, North Korean Vice Foreign Minister Choe Son Hui warned Washington of an "unwanted outcome" if it did not adjust its stance on economic sanctions.

Saturday's launch "does not violate Kim Jong Un's self-imposed missile-testing moratorium", which "only applied to intercontinental-range ballistic missiles", said North Korea analyst Ankit Panda.

The South's presidential Blue House said it was monitoring the situation and "closely sharing information with the United States".