By John Wagner / The Washington Post

President Donald Trump on Tuesday issued a stern warning to North Korea, saying that if its threats to the United States continue, the outcast nation will be “met with the fire and the fury like the world has never seen.”

Trump comments came as North Korea spurned a new round of sanctions approved by the United Nations Security Council and pledged to continue to press forward with development of nuclear weapons that could reach the U.S. mainland.

Appearing at an event at his Bedminster, New Jersey, golf club, where Trump is on a 17-day “working vacation,” he said that “North Korea best not make any more threats of the United States.”

“They will be met with the fire and fury and frankly power, the likes of which this world has never seen before,” Trump said.

The Washington Post on Tuesday reported that North Korea has successfully produced a miniaturized nuclear warhead that can fit inside its missiles, crossing a key threshold on the path to becoming a full-fledged nuclear power, according to a confidential assessment by U.S. intelligence officials.

Trump’s warning on Tuesday further raises the stakes for the U.S. president and other world leaders, who face limited options in dealing with North Korea’s aggression.

Earlier Tuesday, Trump suggested on Twitter progress is being made with the cooperation of China and Russia, both of which supported the Security Council resolution offered by the United States over the weekend.

“After many years of failure, countries are coming together to finally address the dangers posed by North Korea,” Trump said. “We must be tough & decisive!”

Trump also used Twitter to amplify a Fox News report, based on anonymous sources, that U.S. spy satellites had detected North Korea loading two cruise missiles on a patrol boat on the country’s coast in recent days.

Without adding any comment of his own, Trump, who regularly decries leaks to the media, retweeted to his more than 35 million followers a link to the day-old story, which was featured Tuesday morning on “Fox & Friends,” a program on the Fox News network.

A White House spokesman did not respond to a question about whether Trump’s retweet amounted to a confirmation of Fox’s story, which was attributed to unnamed “U.S. officials with knowledge of the latest intelligence in the region.”

Trump’s decision to disseminate the report came amid a larger push by the White House to call attention to the president’s efforts to contain North Korea’s military ambitions, including an unanimous vote by the United Nations Security Council over the weekend on a U.S.-sponsored resolution imposing tougher sanctions.

The Washington Post reported Tuesday that North Korea has successfully produced a miniaturized nuclear warhead that can fit inside its missiles, crossing a key threshold on the path to becoming a full-fledged nuclear power, according a confidential assessment by U.S. intelligence officials.

The report by Fox highlighted a far less significant threat than those posed than the long-range missiles, known as ICBMS, that have been central to escalating tensions in the region.

One intelligence official said that the report itself was insignificant and not a sign that North Korea was preparing to test a missile or make any other provocation. However, the official, who was not authorized to speak publicly, was chagrined that Trump would retweet a report about “something unimportant” that nonetheless “reveals something about our surveillance capabilities.”

Trump, who receives daily intelligence briefings, including while on his current 17-day “working vacation” in Bedminster, would presumably be in a position to know whether U.S. intelligence officials have reason to believe Kim Jong Un’s regime in fact did load cruise missiles onto a patrol boat recently.

Asked about the report Tuesday morning on Fox, Nikki Haley, the U.S. ambassador to the United Nations, said she couldn’t comment.

“I can’t talk about anything that’s classified, and if it’s in the newspaper, that’s a shame,” Haley said. “It’s incredibly dangerous when things go out to the press like that.”

Since taking office, Trump has increasingly spoken out against leaks of sensitive information by members of his administration, some of it damaging to the president himself. He recently urged Attorney General Jeff Sessions to take a far more aggressive posture toward rooting out leakers.

The Washington Post’s Ellen Nakashima and Karen DeYoung contributed to this report.