North Korean FM accuses US of declaring war, says can take countermeasures

North Korean Foreign Minister Ri Yong-ho said the United States President Donald Trump has declared war and Pyongyang reserves the right to take countermeasures, including shooting down the US strategic bombers.

After hearing Ri's speech at the United Nations General Assembly in New York, Trump appeared to threaten regime change over the weekend, tweeting to say if the country's foreign minister echoed the thoughts of North Korean leader Kim Jong-un they "won't be around much longer."

"The whole world should clearly remember it was the US who first declared war on our country," the independent.co.uk quoted Ri, as saying to reporters in New York.

"Since the United States declared war on our country, we will have every right to make countermeasures, including the right to shoot down United States strategic bombers even when they are not inside the airspace border of our country," he added.

Earlier on Saturday, terming the US President "a mentally deranged person full of megalomania," the Foreign Minister told the United Nations General Assembly as the Pentagon announced that it had flown bombers escorted by fighter jets over waters east of North Korea.

This development assumes much significance as US Air Force B-1B Lancer taking patrol flight over waters east of North Korea, is the farthest north of the Demilitarized Zone any US aircraft has flown off North Korea's coast in the 21st century.

North Korea has warned that Trump's bellicose remarks against the Asian country and its leader will make the US mainland an "inevitable" target for rocket strikes.

"Through such a prolonged and arduous struggle, now we are finally only a few steps away from the final gate of completion of the state nuclear force," Ri told the annual gathering of world leaders in New York.

Trump had announced on Thursday that the new US sanctions will allow targeting the companies and institutions, which finance and facilitate trade with North Korea.

The UN Security Council unanimously adopted its ninth round of sanctions on Pyongyang to counter its nuclear and ballistic missiles programmes.

Recently, North Korea conducted its sixth most powerful nuclear test on September 3, attracting UN sanctions and criticism from the international community.

Under Kim Jong Un's leadership, Pyongyang carried out several intercontinental ballistic missile tests, including 20 missile tests in 2016.