Secretary of State John KerryJohn KerryKerry: Trump can’t instantly undo Obama actions ‘All or nothing’ leaves us nothing Kerry: Trump comments on German chancellor ‘inappropriate’ MORE on Friday warned North Korea that a threatened missile launch would be a "provocative and unwanted attack" that would prove to be a "huge mistake."
"Kim Jong Un needs to understand, as I think he probably does, what the outcome of a conflict would be,” Kerry said as he arrived in Seoul to meet with South Korean President Park Geun-hye.
“Our hope is we can get back to talks."
The secretary of State's four-day trip comes amid new worries of the threat posed by North Korea.
"The rhetoric we are hearing from North Korea is simply unacceptable by any standard," Kerry said, according to Reuters. "We are all united in the fact that North Korea will not be accepted as a nuclear power."
A report by the Pentagon's Defense Intelligence Agency, which was disclosed in a congressional hearing on Thursday, claimed with "moderate confidence" that North Korea is capable of mounting a nuclear weapon on a missile.
The Pentagon has insisted since the disclosure that there is little evidence that the North Koreans have done so already, or that such a missile could be accurately fired.
The White House on Friday flatly declared that North Korea is not yet capable of launching a nuclear strike.
"It is our assessment that North Korea has not demonstrated the capability to deploy a nuclear-armed missile," White House press secretary Jay Carney said.
Kerry echoed that sentiment in his remarks in Seoul.
“It is inaccurate to suggest that the DPRK [Democratic People's Republic of Korea] has fully tested, developed, and demonstrated capabilities that are articulated in that report,” Kerry said.
“But obviously, they have conducted a nuclear test so there is some kind of device. But that is very different from miniaturization and delivery and from tested delivery and other things. Does it get you closer to a line that is more dangerous? Yes.”
The White House said it was taking "prudent actions" to respond to North Korea's provocations.
"You should not mistake that for anything but serious concern about the actions, behavior, and rhetoric from North Korea, which is why we've taken the steps that we've taken," Carney said.
The White House urged North Korea to take "an alternate path" following reports from South Korean military analysts suggesting Pyongyang is gearing up for the launch of several long-range missiles as soon as next week.
"We take this seriously," Carney said. "It is, as I've said in the past, reminiscent of past periods of provocative actions and increased bellicose rhetoric."
Sen. John McCainJohn McCainThe rise of Carlson, and the fall of Van Susteren Booker to vote against Tillerson Earnest: GOP intellectually dishonest on Manning pardon MORE (R-Ariz.) on Friday urged the Pentagon to shoot down any missile fired from Pyongyang as a show of American military strength.
“I would take it out,” McCain said. “We show young Kim Jong Un that we can take out his capabilities. We can show that to him.”
Kerry planned to visit China and Japan following his stop in South Korea and will likely lobby leaders in Beijing to take a more aggressive approach toward the North Koreans.
China has condemned recent North Korean posturing and voted in favor of sanctions following the country's third nuclear test, a sign leaders there could be increasingly concerned by the actions of their ally.
Carney said top administration officials hope to build diplomatic pressure against Pyongyang.
"That relationship between China and North Korea and also between Russia and North Korea is one that we hope can be utilized to bring about some change in behavior,' Carney said.
—Justin Sink contributed.
This story was first posted at 8:10 a.m. and has been updated.