SEOUL (Reuters) – North Korea said on Monday it had successfully test-fired a new type of medium-to-long-range ballistic missile on Sunday, claiming further advancement in a weapons programme it is pursuing in violation of United Nations resolutions.

North Korea fired the ballistic missile into the sea early on Sunday, the first test of U.S. President Donald Trump’s vow to get tough on an isolated North Korean regime that last year tested nuclear devices and ballistic missiles at an unprecedented rate.

The North’s state-run KCNA news agency said leader Kim Jong Un supervised the test of the Pukguksong-2, a new type of strategic weapon capable of carrying a nuclear warhead.

North Korea has conducted five nuclear tests, including two last year, although its claims to be able to miniaturise a nuclear weapon to be mounted on a missile have never been independently verified.

KCNA added that the missile was fired at a high angle in consideration of the safety of neighbouring countries. A South Korean military source said on Sunday the missile reached an altitude of 550 kilometres (342 miles). It flew a distance of about 500 km, landing in the Sea of Japan.

North Korea also said the missile was propelled by a solid fuel engine, which follows last year’s test of what it said was a solid-fuel powered submarine-launched missile.

Solid fuel engines boost the power of ballistic rockets and give them greater range. They give less warning of an impending launch because it takes less time to fuel the rocket.

A U.S. official said over the weekend that the Trump administration had been expecting a North Korean “provocation” soon after taking office. The United States will consider a full range of options in response, but they would be calibrated to show U.S. resolve while avoiding escalation, the official added.

The latest test comes a day after Trump held a summit meeting with Japanese Prime Minister Shinzo Abe, and also follows Trump’s phone call last week with Chinese President Xi Jinping.

(Reporting by Ju-min Park and Tony Munroe; Editing by Lincoln Feast)