Foreign Minister Javad Zarif said Monday that the new administration's chance to revive the JCPOA "is not unlimited."
North Korea's new missile, while a threat of clear significance on paper, does have some serious problems it simply can't overcome.
Military experts say the new liquid-fueled ICBM appears to more powerful than anything previously known to be in the nation's weapons arsenal.
The Russian Avangard hypersonic missile system can reportedly travel at 20 times the speed of sound.
North Korea has set an end-of-year deadline for U.S. officials to break the deadlock in denuclearization talks, or receive a "Christmas gift."
It comes after Pyongyang released propaganda images showing Kim galloping on horseback through snowy mountains on his way up to Mount Paektu.
The Hwasong-15 had its first and only test launch in 2017, but the missile's potency was not immediately clear.
The RS-28 Sarmat is reportedly able to carry a nuclear payload capable of destroying an area the size of Texas.
General Terrence O'Shaughnessy said the U.S. now faces "adversaries that are actually able to reach out and touch us."
President Vladimir Putin has ordered over a dozen regiments to finish upgrading their Topol missile systems this year, among other military updates.
The RS-28 Sarmat could be seen taking flight as both the Russian and U.S. leaders discussed an "arms race."
The tests come as Russian President Vladimir Putin revealed new nuclear missiles and Moscow's relationship with the West took another major blow.
The Hwasong-14 and Hwasong-15 put the U.S. in North Korea's trajectory, so how easily will Kim Jong Un give them up?
Russia's new RS-28 Sarmat intercontinental ballistic missile is allegedly capable of wiping out Texas, but Putin's demonstration took aim elsewhere.
Russia's ambassador to North Korea said Moscow's nuclear-armed neighbor would consider an attempt to stop oil flow to be a "declaration of war."
"It will be a very, very kinetic, physical, violent fight over some really, really tough ground, and everybody is going to have to be mentally prepared," Marine Corps Commandant General Robert Neller said.
North Korea said it was able to build nuclear bombs and intercontinental ballistic missiles because it trusts no one but itself.
A man who claimed to be a bodyguard to Kim Jong Il said his youngest son was "angry," "stressed" and "his personality was explosive."
Kim Jong Un's lack of response to Trump's "nuclear button" tweet may mean North Korea is serious about peace talks. But is the U.S.?
Nearly a year after Trump took office, 17 former nuclear launch officers said, "The reality of this presidency is worse than we feared."
Kim Jong Un is "trying to make himself the reincarnation of Kim Il Sung, who was really beloved by the North Koreans."
One year ago today, Donald Trump vowed North Korean supreme leader Kim Jong Un would never launch an intercontinental ballistic missile.