North Korea has said it has conducted a successful test of an intercontinental ballistic missile (ICBM) with the ability to strike all of America's mainland, drawing a sharp warning from US President Donald Trump.

North Korean leader Kim Jong Un supervised the launch last night and said it was a "stern warning" for the United States that it would not be safe from destruction if it tries to attack, the country’s KCNA news agency said.

According to the agency, Kim Jong Un said: "The test-fire reconfirmed the reliability of the ICBM system, demonstrated the capability of making a surprise launch of the ICBM in any region and place any time, and clearly proved that the whole US mainland is in the firing range of the DPRK missiles."

The launch comes less than a month after the North conducted its first ICBM test in defiance of years of efforts led by the United States, South Korea and Japan to rein in Pyongyang's nuclear weapons ambitions.

North Korea conducted its fourth and fifth nuclear test last year and has engaged in an unprecedented pace of missile development that experts said significantly advanced its ability to launch longer-range ballistic missiles.

South Korea conducted a live-fire missile exercise in response to the missile launch

"By threatening the world, these weapons and tests further isolate North Korea, weaken its economy, and deprive its people," Mr Trump said in a statement.

"The United States will take all necessary steps to ensure the security of the American homeland and protect our allies in the region," he said.

Kim Jong Un observes as the missile launches in the distance

The South Korean Defence Minister said the country will prepare independent measures to curb the nuclear threat.

China has said it opposed North Korea's "launch activities that run counter to Security Council resolutions and the common wishes of the international community".

A foreign ministry statement added: "At the same time, China hopes all parties act with caution, to prevent tensions from continuing to escalate, to jointly protect regional peace and stability."

The United States and South Korea conducted a live-fire ballistic missile exercise in a display of firepower in response to the missile launch, the US and South Korean militaries said last night.

The missile test came a day after the US Senate approved a package of sanctions on North Korea, Russia and Iran.

In yesterday's test, North Korea's Hwasong-14 missile reached an altitude of 3,724.9km and flew 998 km for 47 minutes and 12 seconds before landing in the waters off the Korean peninsula's east coast, KCNA said.