‘We are prepared’

South Korea and the United States flew warplanes including stealth fighter jets over waters around the Korean peninsula yesterday in a fresh show of force following recent missile tests by the North, Seoul said.

Sixteen South Korean warplanes, including F-35 stealth fighters and four US F-16 jets, formed an attack squadron over the West Sea -- also known as the Yellow Sea -- to "respond to the enemy threat," Seoul's Joint Chiefs of Staff said in a statement.

The allies "demonstrated their strong ability and will to strike quickly and accurately against any provocation from North Korea," it added.

The air manoeuvres, which involved some 20 warplanes, come a day after the allies fired eight ballistic missiles into the Sea of Japan in the wake of Pyongyang's Sunday weapons tests.

US and South Korean officials have been warning for weeks that Kim Jong Un's regime is preparing to carry out a fresh nuclear test.

US Deputy Secretary of State Wendy Sherman, in Seoul on a three-day visit, warned there would be a "swift and forceful" response were Pyongyang to go ahead with what would be its seventh such test.

The entire world will respond in a "strong and clear manner," she said, adding: "We are prepared."