North Korea has conducted a test of a new high-thrust engine at its Tongchang-ri rocket launch station and leader Kim Jong Un said the successful test was "a new birth" of its rocket industry, the reclusive North's official media said on Sunday.

The engine would help North Korea achieve world-class satellite launch capability, KCNA said, indicating the test was of a new type of rocket engine for long-range missiles.

The United States and China pledged to work together to get the North to take "a different course" and move away from its weapons programs after U.S. Secretary of State Rex Tillerson met his Chinese counterpart on Saturday.

North Korea has conducted five nuclear tests and a series of missile launches, in defiance of U.N. sanctions, and is believed by experts and government officials to be working to develop nuclear-warhead missiles that could reach the United States.

Kim Jong Un has said North Korea is close to a test-launch of an intercontinental ballistic missile.

KCNA said the test was carried out at the Sohae Satellite Launching Ground, where North Korea has conducted long-range rocket tests.

South Korea's military declined to comment.

The Washington-based think tank 38 North said last week satellite imagery indicated activity at the site's vertical engine stand, possibly in preparation for a rocket engine test.

"The rail-mounted environmental shelter has been moved up against the engine test stand since February 5, either for maintenance or to position a rocket engine for testing," 38 North said in a note.

It said North Korea had installed the environmental shelter in late 2015 to conceal detection of test preparations.

KCNA cited leader Kim as saying the significance of the test would soon be evident.

"He noted that the success made in the current test marked a great event of historic significance as it declared a new birth of the Juche-based rocket industry," KCNA said. Juche refers to North Korea's homegrown ideology of self-reliance.

"He emphasized that the whole world will soon witness what eventful significance the great victory won today carries," it said.