The White House issued a statement after a North Korean delegation to the neighboring South reportedly expressed willingness to talk to Washington, amid a longstanding nuclear standoff with Pyongyang that has raised fears of a devastating atomic exchange.
It said: "The United States, our Olympic host the Republic of Korea, and the international community broadly agree that denuclearization must be the result of any dialogue with North Korea. The maximum pressure campaign must continue until North Korea denuclearises.
"As President Trump has said, there is a brighter path available for North Korea if it chooses denuclearization. We will see if Pyongyang's message today, that it is willing to hold talks, represents the first steps along the path to denucleariSation."
It was not clear if the wording signaled a departure from Washington's long-held position that North Korea must take concrete steps toward disarming before talks can begin.
North Korea - which carried out multiple missile tests last year, including those believed capable of reaching the US mainland -has long expressed its desire to talk to Washington without preconditions.
The North Korean delegation to the South was led by General Kim Yong Chol, who held an hour-long meeting with President Moon Jae-in ahead of the closing ceremony of the Winter Olympics.
The nuclear-armed North has gone on a charm offensive over the Games, sending athletes, cheerleaders and performers. Leader Kim Jong Un's sister Kim Yo Jong attended the opening ceremony.
Washington imposed fresh sanctions on Pyongyang Friday, with Donald Trump describing them as the heaviest ever.
North Korea slams measures
North Korea on Sunday slammed the latest US measures against it as an "act of war", after US President Donald Trump announced the "heaviest sanctions ever" on the nuclear-armed regime.
The measures, which Washington says are aimed at forcing Pyongyang to roll back its banned nuclear and weapons programmes, target more than 50 North Korea-linked shipping companies, vessels and trade businesses.
"Like we have said repeatedly, we consider any restrictions on us as an act of war," the North's foreign ministry said in a statement carried by the state-run KCNA news agency.
It also vowed a retaliation if the US "really has the nerves" to confront the North in a "rough" manner.
Trump warned on Friday that, if the latest sanctions don't work, the US would "go to phase two" that "may be a very rough thing", without elaborating.
In response, the North also vowed to "subdue the US in our own way" if provoked, saying "Trump is trying to change us with such sanctions and hostile remarks, which shows his ignorance about us".
"We already have our own nuclear weapon - a treasured sword of justice to protect us from such threats from the US," the foreign ministry said.
The comment came hours before the North's senior delegation led by Kim Yong Chol, a blacklisted military general, is set to attend the closing ceremony of the South's Winter Olympics, which will also be attended by Trump's daughter Ivanka Trump.
