He told reporters in Seoul on Wednesday that the country will take steps to disarm in two and a half years. But details of the agreement between President Trump and Kim Jong Un remain vague.
President Trump says he expects to know quickly whether North Korea is serious about surrendering its nuclear weapons. But Pyongyang has fooled the U.S. in the past.
Journalists observed as North Korea blew up tunnels it uses for nuclear testing. But experts say it was mostly for show, and closing the site will have little impact on the nation's capabilities.
President Trump meets Tuesday with his South Korean counterpart, Moon Jae-in. They're putting their heads together ahead of a planned summit next month between Trump and North Korea's Kim Jong Un.
President Trump tweeted out the details of his planned meeting with North Korea's leader. "I really think we have a very good chance of doing something very meaningful," he said.
As President Trump considers withdrawing from the Iran accord, Israel says files show Iran concealed its nuclear ambitions. But the U.K., France and Germany say they always knew that — hence the deal.
North Korea's leader told South Korea's president he would invite security experts and journalists to the site. South Korea's president also spoke with President Trump about a U.S.-North Korea summit.
"President Trump is in for a rude surprise if he thinks ... Kim Jong Un is going to say, 'Sure, I'll hand over my nuclear weapons,'" North Korea expert Jean H. Lee tells NPR.
The technology, described as a "large-scale optical tracking and measurement system," is reportedly for use in testing Pakistani ballistic missiles that can carry multiple warheads.
The weapons include cruise missiles, nuclear-powered underwater drones and a new hypersonic missile. Putin warned that any use of nuclear weapons against Russia or its allies would trigger a response.
After trading bellicose barbs with North Korea throughout 2017, the U.S. heads into 2018 with an increasingly capable foe and no clear diplomatic exit ramps to temper the tensions.
It took decades, but John Coster-Mullen has pieced together specs for America's first nuclear bombs. Some believe his odyssey says something about North Korea's rapid nuclear progress.
Nuclear civil defense fell out of favor in the latter years of the Cold War. But, as North Korea builds its nuclear arsenal, local officials are reluctant to bring it back.
"We have lines of communications to Pyongyang," Secretary of State Rex Tillerson said. The State Department later said North Korean officials are not "ready for talks regarding denuclearization."
It is the latest in a tit-for-tat between President Trump and the North Korean leader. In a tweet on Friday, the president said Kim Jong Un "will be tested as never before!"
Senate Foreign Relations Committee Chairman Bob Corker says his committee is considering narrowing the president's ability to launch wars without congressional approval.
Petrov was on overnight duty in 1983 when computers indicated the U.S. had launched a nuclear strike against his country. He had only a few nerve-jangling minutes to act.
In addition, most falsely believe the president needs congressional authorization to launch a nuclear strike. North Korea's renegade program will be a major focus at this week's U.N. General Assembly.
Sanctions and the threat of military action have proven ineffective at stopping North Korea's nuclear program. Some say that a deal with North Korea, with China's involvement, may be the way to go.
At a time of growing North Korean weapons capabilities, President Trump and Moon Jae-in will meet Thursday. "We will focus on building a foundation of friendship and trust," says Moon's spokesman.
