North Korea test fires submarine-launched ballistic missile

The launch comes just two days after South Korea and the United States began annual military exercises in the South

Footage of a North Korean missile launch on July 9 2016 (Getty Images )

North Korea has test-fired a submarine-launched ballistic missile off its east coast, South Korea's military has said.

The missile was launched near the coastal city of Sinpo, where satellite imagery shows a submarine base is located, an official at South Korea's Joint Chiefs of Staff said.

The launch comes just two days after South Korea and the United States began annual military exercises in the South, which have been condemned by North Korea as a preparation for invasion.

The North's military has said it will turn Seoul and Washington into "a heap of ashes through a Korean-style pre-emptive nuclear strike" if they show any signs of aggression toward the North's territory.

South Korea's Unification Ministry expressed strong regret over the North's warning, saying the drills with the US are defensive in nature. Seoul and Washington have repeatedly said they have no intention of invading Pyongyang.

South Korea’s President Park Geun-hye said Pyongyang was likely to be confrontational during the drills because of a “grave rupture” and “unrest in the North’s regime” following the high-profile defection last week of North Korea's deputy ambassador in London to South Korea - an embarrassing setback to the regime of North Korean leader Kim Jong Un, South Korean news agency Yonhap reports.

Earlier this month, a medium-range ballistic missile fired by North Korea flew about 1,000km (620 miles) and landed near Japan's territorial waters - one of the longest flights by a North Korean missile.

North Korea has become further isolated after a nuclear test in January, its fourth, and the launch of a long-range rocket in February brought tightened UN sanctions.

It has launched numerous missiles of various types this year.

Additional reporting by Reuters