North Korea said Monday it had test-fired a new type of long-range cruise missile over the weekend.

The tests took place on Saturday and Sunday after two years of research, according to the state-run Korean Central News Agency (KCNA).

KCNA called it a “strategic weapon of great significance.”

Observers saw this as an indication the new guided-missile has the potential to carry nuclear warheads.

South Korea did not initially confirm the tests by its neighbour.

Its military Joint Chiefs of Staff (JCS) said they were working with the United States to investigate the claims.

North Korea is subject to international sanctions due to its nuclear weapons programme.

UN resolutions prohibit the testing of ballistic missiles, but cruise missiles are not subject to sanctions against the country.

Unlike ballistic missiles, cruise missiles use their own permanent propulsion.

The weekend tests reportedly saw the guided missiles fly for 7,580 seconds – about two hours and six minutes – on an oval trajectory over the North Korean mainland and waters.

They would have hit their targets at a distance of 1,500 metres, according to the report.

Pyongyang said its Academy of Defence Science had successfully conducted detailed tests of missile parts, engine tests on the ground and control and guidance tests.

The development of the weapons system “holds the strategic significance of possessing another effective deterrence means for more reliably guaranteeing the security of our state and strongly containing the military manoeuvres of the hostile forces” against North Korea, KCNA wrote.

The latest North Korean weapons test came after a joint military exercise between US and South Korean forces.

It was criticized by Pyongyang and ended on Aug. 26 after nine days.

North Korea carried out cruise missile tests in March after a similar command exercise in South Korea.

Since leader Kim Jong Un’s failed summit with former US President Donald Trump in Vietnam in February 2019, talks on halting the programme have stalled.

At a party congress earlier this year, Kim announced his country would continue to pursue a path of nuclear deterrence with new weapons, including new intercontinental ballistic missiles.

North Korea reportedly held a night-time military parade early Thursday in Pyongyang to mark the 73rd anniversary of the it’s founding.

The country often uses anniversaries to showcase its military strength.