North Korea's latest rocket-engine test showed "meaningful" progress, South Korea said on Monday, while an analyst said it was a dangerous step towards the North's goal of developing a rocket that could hit the United States.

The North's KCNA news agency said on Sunday the engine would help North Korea achieve world-class satellite-launch capability, indicating a new type of rocket engine for an intercontinental ballistic missile.

The North's announcement of a successful engine test came as Rex Tillerson, the US secretary of state, was in Beijing at the end of his first visit to Asia for talks dominated by concern about North Korea's nuclear and missile programmes.