North Korea has fired a ballistic missile into waters off the coast of Japan, South Korea's military says.

It comes as South Korea, Japan and US intelligence chiefs reportedly meet in Seoul to discuss North Korea.

In recent weeks, Pyongyang has embarked on a flurry of tests of what it claims to be hypersonic and long-range cruise missiles, and anti-aircraft weapons.

North Korea has been developing its weapons programme despite strict international sanctions.

It is specifically prohibited by the United Nations from testing ballistic missiles as well as nuclear weapons.

But in recent weeks it has pressed ahead with its missile launches as South Korea also develops its own weapons, in what observers say has turned into an arms race on the Korean peninsula.

Seoul unveiled a submarine-launched missile recently, and is holding what is said to be South Korea's largest defence exhibition ever this week. It is also due to launch its own space rocket soon.

Following the Korean War, which split the peninsula into two countries, North and South Korea have remained technically at war as the conflict ended in 1953 with an armistice.

North Korean leader Kim Jong-un said last week that he did not wish for war to break out on the Korean peninsula again, but said his country needed to continue developing weapons for self-defence against enemies, namely the US which he accused of hostility.

The US under President Joe Biden has repeatedly said it is willing to talk to North Korea, but has demanded Pyongyang give up nuclear weapons before sanctions can be eased. North Korea has so far refused.