North Korea made an unsuccessful attempt to launch a missile the day after displaying a massive show of strength, South Korean and US military sources have said.

Details of the attempted launch are scant, but it will be seen as a gesture of defiance by Kim Jong-un, the North Korean leader.

U.S. Pacific Command detected and tracked what it assessed to be a North Korean ballistic missile launch at 11:21 a.m. Hawaii time (2121 GMT) on Saturday, said U.S. Navy Commander Dave Benham, a spokesman for Pacific Command.

"The missile blew up almost immediately. The type of missile is still being assessed," he said.

It was launched from a base at Sinpo, a port city on the North Korean east coast.

President Donald Trump has been briefed on the latest developments, a White House official said.

The North's previous attempted missile launch, on April 5, also suffered an in-flight failure before the weapon crashed into the Sea of Japan. Experts have suggested that the United States may be carrying out "left-of-launch" attacks on the missiles using electromagnetic propagation or cyber attacks, including through infected electronics aboard the weapon that confuse its command and control or targeting systems.

The launch came as tension between North Korea and the United States rose to new levels on Saturday after the Pyongyang regime unveiled what could be a missile capable of striking the American mainland.