SEOUL, South Korea -- North Korea claimed it successfully tested a powerful new rocket engine on Sunday, signaling defiance as the U.S. secretary of state visited China.
North Korean leader Kim Jong Un observed the test of a new high-thrust engine at dawn at the Sohae satellite launching pad, the state-run Korean Central News Agency reported.
It quoted him as saying the test "declared a new birth of the Juche-based rocket industry." Juche, or self-reliance, refers to the communist state's official ideology.
The test occurred as Secretary of State Rex Tillerson was due to meet with Chinese President Xi Jinping in Beijing.
Tillerson is pushing for closer China-U.S. cooperation on dealing with the growing threat from North Korea's nuclear weapons program.
China was the last stop on his three-country tour that also took him to South Korea and Japan.
Tillerson has suggested President Donald Trump's administration may adopt a tougher strategy toward the North. In Seoul, he warned that the U.S. would consider preemptive military action if the threat reaches a level "that we believe requires action."
KCNA said the "Korean-style" engine was developed by the Academy of the National Defense Science.
"The results of the test confirmed the stable maintenance of technical indices of all systems such as starting and stopping features," it said.
The report stressed the engine was made with North Korean technology. Kim Jong Un "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," the report said.
"He emphasized that the whole world will soon witness what eventful significance the great victory won today carries," it added.
North Korea has stepped up its efforts to develop a nuclear-tipped missile that could reach the U.S. mainland, although experts are divided on how close it is to reaching its stated goal.
The North has conducted two nuclear tests and test-fired more than two dozen missiles since last year.