Pyongyang: North Korea has said its firing of a missile over Japan was "the first step" of military operations in the Pacific, signalling plans for more launches, media reports said.
North Korea's official news agency KCNA has also repeated threats to the US Pacific island of Guam, and called it "an advanced base of invasion", the BBC reported on Wednesday.
The missile launched on Tuesday crossed Japan's northern Hokkaido island, triggering public alerts to take cover, before landing in the sea.
The KCNA said the launch was in direct response to the joint US-South Korean military drills, as well as to mark the anniversary of the Japan-Korea treaty of 1910, which saw Japan annex the Korean peninsula.
Quoting its leader Kim Jong-un, KCNA said that "like a real war", the latest drill was "the first step of the military operation of the Korean People's Army in the Pacific and a meaningful prelude to containing Guam".
Kim has also ordered more rocket drills targeting the region, the state media said.
For the first time, North Korea's official news agency admitted deliberately firing the ballistic missile across Japan.
Previous projectiles which crossed the mainland were later claimed to have been satellite launches.
The UN Security Council has unanimously condemned North Korea for its actions. Meeting late on Tuesday in New York, the council called the launch "outrageous", demanding Pyongyang cease all missile testing.
However, the statement did not threaten new sanctions against Pyongyang, the BBC added.
North Korea has repeatedly conducted missile launches in recent months, despite being barred from doing so under UN rules.
The latest, a domestically made Hwasong-12, was launched early on Tuesday morning from a site near Pyongyang.
It travelled some 2,700 km, at an unusually low height for North Korean missile tests, over Hokkaido before crashing about 1,180 km off Japan's eastern coast.
Japanese Prime Minister Shinzo Abe later called it "unprecedented, serious and a grave threat".
US President Donald Trump, in a statement released by the White House, said the world had "received North Korea's latest message loud and clear".
Earlier in August, Pyongyang first threatened to fire missiles towards Guam where some 160,00 US citizens live.
US officials had earlier suggested that the fact it had not carried out its threat so far was a sign of possible progress.