North Korea's latest rocket engine test showed "meaningful progress" in its missile capabilities, Seoul said Monday, as the nuclear-armed state steps up its controversial weapons development programmes.

The North's leader Kim Jong-Un oversaw the "successful" test of the powerful new rocket engine, state media said Sunday, in a move apparently timed to coincide with a trip to Asia by new US Secretary State Rex Tillerson.

4 MISSILES

It was the latest in a series of moves by Pyongyang, which have recently included the firing of four missiles to its east in what it described as practice for an attack on US army bases in Japan.

"The latest test is believed to have made some meaningful progress in engine functions," Seoul's defence ministry spokesman told reporters.

"But we need more analysis on its exact propulsive power and applicable use," said Lee Jin-Woo. 

The North's last ground test of a high-powered rocket engine — which can be used in missiles — was in September last year, and also observed by Kim.

FAILED APPROACH

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