US bombers overflew the Korean peninsula Thursday as part of an exercise with Japanese and South Korean warplanes, the US Air Force said, days before President Donald Trump arrives in the region for a trip set to be dominated by the nuclear-armed North.

Tensions are high over Pyongyang’s ballistic missile and atomic programmes, which in recent months have seen it test ICBMs and carry out its sixth nuclear blast.

Flights by supersonic B-1B Lancer bombers in the area always infuriate North Korea, which condemned the drill as “blackmail” early Friday.
Two B-1B aircraft took off from Andersen Air Force Base in Guam, and were joined west of Japan by Japan Air Self-Defense Force fighters, the US Pacific Air Force said in a statement.

“The Lancers then transited overland to Korea to integrate with Republic of Korea fighters in the Yellow Sea,” the statement read, adding that the aircraft later returned “to their respective home stations.”

The exercise was part of the “continuous bomber presence” mission in the Pacific and “was not in response to any current event,” the statement said.

The operation follows an October 10 “show of force” in which two Lancers staged the first night-time joint aviation exercises with Japan and South Korea.

Trump and North Korean leader Kim Jong-Un have exchanged threats and personal insults in recent months — the US president has warned of “fire and fury” in response to Pyongyang’s threats, and the North’s KCNA news agency this week called him “incurably mentally deranged”.

North Korea in July launched two intercontinental ballistic missiles apparently capable of reaching the US mainland — described by Kim as a gift to “American bastards”.

It followed up with two missiles that passed over Japan, and its sixth nuclear test, by far its most powerful yet.

Pyongyang may be preparing for another missile test, Seoul’s spy agency reportedly said Thursday.

The North habitually condemns B1-B flights as rehearsals for an attack, and KCNA said Friday: “The reality clearly shows that the gangster-like US imperialists are the very one who is aggravating the situation of the Korean peninsula and seeking to ignite a nuclear war.”

Trump begins an Asian tour on Friday that will include South Korea and is set to be dominated by the North Korean nuclear issue.