North Korea confirmed on Monday a series of missiles tests, claiming the test a day earlier of what state media said were super-large multiple rocket launchers had been a success.

North Korea fired what appeared to be two short-range ballistic missiles off its east coast on Sunday, the latest in a series of launches that South Korea has called "inappropriate" as the world grapples with the coronavirus pandemic.

KCNA news agency said the launch was aimed at examining the strategic and technical features of the "super-large multiple rocket launchers", which have been tested a number of times since last August usually overseen by leader Kim Jong Un.

KCNA, the official news agency, did not mention Kim's attendance at the latest test, which was led by governing party vice chairman Ri Pyong Chol and conducted at the Academy of National Defense Science.

"The operational deployment of the weapon system of super-large multiple rocket launchers is a crucial work of very great significance in realising the party's new strategic intention for national defence," Ri was quoted as saying during the test, without elaborating.

"The test-fire was conducted successfully," KCNA added.

It marked the fourth round of tests this month since North Korea staged military drills and resumed missile launches following a three-month break.

Talks between the United States and North Korea on denuclearisation have been largely stalled since the collapse of the summit between Kim and US President Donald Trump in Hanoi in February 2019.