Korean peninsula tensions
South Korean soldiers talk next to barricades at a checkpoint on the Grand Unification Bridge which leads to the truce village Panmunjom, just south of the demilitarised zone separating the two Koreas, in Paju, South KoreaKim Hong-Ji/Reuters

North Korea has claimed it has completed preparations for full military action against South Korean and American troops in the Korean peninsula. The latest warning came just as the US and South Korean forces flew eight fighter jets in a show of force.

Four of the US F-16 fighters and South Korea's F-15K warplanes bombed simulated enemy targets on Saturday, 22 August, the South Korean army confirmed.

"The flights were aimed at showing off the military might of South Korea and US's combined air force power," a South Korean military source told the Yonhap news agency. The source added the flights were intended to threaten the North in the face of its provocations amid the rising tensions in the region.

The South has reiterated its commitment to strongly respond if there are more provocative actions from its neighbour. "We can never tolerate any North Korean provocations that could endanger the safety of our soldiers and people," said President Park Geun-hye, dressed in military uniform, during a surprise visit to the headquarters of the Third Army near capital Seoul.

Park's warning was echoed by the country's Defence Minister Han Min-koo, who reassured the public that Seoul would respond in kind to the North. "If North Korea pushes ahead with additional provocations, our military will retaliate harshly and make them pay a bitter price," he said. "Anti-North loudspeaker broadcasts constitute due countermeasures we took in response to the North's mine provocations."

The fresh escalation in tensions came after Pyongyang issued a 48-hour ultimatum to South Korea to stop its loudspeaker propaganda. North Korea's UN ambassador An Myong Hun told reporters: "If South Korea does not respond to our ultimatum, our military counteraction will be inevitable and that counteraction will be very strong."

Outsiders have urged both sides for restraint and called for calm in the Korean peninsula. The United Nations Command (UNC) has also reportedly offered to initiate talks with North Korea even as UN chief Ban Ki-moon exhorted both sides to avoid further escalation of the situation.