North Korean Foreign Minister Ri Yong Ho leaves his hotel in New York on Sept. 25, 2017. Ri says that President Donald Trump has declared war on North Korea — and that the country can now defend itself under international law.

President Trump's tweets about North Korea amount to a declaration of war, says North Korean Foreign Minister Ri Yong Ho. In the latest contentious remarks between the two countries, Ri claims that under international law, his country can legally shoot down U.S. military planes — even if they're not in North Korea's airspace.

"For the past couple of days, we had earnestly hoped that the war of words between North Korea and the U.S. would not lead to action," Ri said, in a translation for NPR by journalist Jihye Lee. "However, Trump had ultimately declared war again last weekend, by saying regarding our leadership, that he will make it unable to last longer."

Ri said Trump, as America's current leader, had issued a "clear declaration of war."

In response, Pentagon spokesman Col. Robert Manning said on Monday, "If North Korea does not stop their provocative actions, you know, we will make sure that we provide options to the President to deal with North Korea."

Ri was speaking Monday morning in New York, where U.N. meetings have been going on since last week. He was responding to a tweet from Trump, who said on Saturday, "Just heard Foreign Minister of North Korea speak at U.N. If he echoes thoughts of Little Rocket Man, they won't be around much longer!"

The exchange of threats also included this from Trump, on Friday: "Kim Jong Un of North Korea, who is obviously a madman who doesn't mind starving or killing his people, will be tested like never before!"

Today, Ri said:

"The world, including all member states currently attending the United Nations General Assembly, must clearly remember that this time, America declared war on us first. The U.N. charter acknowledges all member states' independent rights to self-defense.

Because the United States declared war, even if U.S. strategic bombers do not intrude into our air, we will possess the right to respond in self-defense, including the right to launch at a random time and drop [it/ the strategic bomber]."

As for who or what country might "last longer," the North Korean official added, "we will see when the time comes."

The comments come after a weekend in which the U.S. sent warplanes into international airspace east of North Korea, in a show of force that included B-1B Lancer bombers and F-15C Eagle fighter escorts.

Of that flight, Pentagon spokesperson Dana White said, "This is the farthest north of the Demilitarized Zone (DMZ) any U.S. fighter or bomber aircraft have flown off North Korea's coast in the 21st century."

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