The US has flown a long-range B-1B bomber over the Korean Peninsula for its first precision-guided weapons bombing drill in seven years, South Korea officials said.

Seoul’s defence ministry said the US B-1B bomber conducted joint aerial drills with other American and South Korean fighter jets.

It said the B-1B bomber dropped Joint Direct Attack Munitions (JDAM) during the training. The JDAM bombs include precision-guided “bunker-busters”.

The drill is seen as a show of force against North Korea amid rising tensions over the North’s recent launches of refuse-carrying balloons toward South Korea.

In the past week, North Korea floated hundreds of huge balloons dumping manure, cigarette butts, scraps of cloth, dead batteries and even reportedly dirty nappies across South Korea.

In response, South Korea vowed “unbearable” retaliatory steps and suspended a fragile military deal meant to ease tensions with its northern neighbour.

The ministry said South Korean fighter jets also conducted live-firing exercises to demonstrate the country’s readiness to punish North Korea if provoked, it said.

North Korea is extremely sensitive to drills using bunker-buster bombs, which could threaten its leadership and complex web of underground military tunnels and structures. North Korea has previously responded to the flights of powerful US aircraft in South Korea with its own missile tests.

A B-1B is capable of carrying a large conventional weapons payload. North Korean has previously called the bomber’s deployment proof of US hostility.

The suspension of the 2018 inter-Korean deal allows South Korea to resume live-fire drills or anti-North Korean propaganda broadcasts via loudspeakers in border areas. Such steps will likely prompt North Korea to take provocative steps in response.

Recently, North Korea launched a rocket in an attempt to place a second spy satellite into orbit in violation of UN resolutions, but it blew up shortly after lift-off.

It also test-fired nuclear-capable weapons for a drill simulating a pre-emptive strike on South Korea, and allegedly jammed GPS navigation signals in South Korea.