(Bloomberg) -- North Korean leader Kim Jong Un warned that the world in 2020 would witness a “new strategic weapon” after his self-imposed deadline for improving relations with the U.S. passed without an agreement.

Kim said in remarks to party leaders on Wednesday said that the new weapons system had been “perfectly carried out” by scientists, designers and “workers in the field of the munitions industry,” the country’s state-run Korean Central News Agency reported on Wednesday.

He didn’t specify what the weapon was, or when it would be deployed. The remarks were made before Kim’s annual New Year’s speech, which has been dreaded in many world capitals because of threats he and his government had made in recent weeks.

Kim added, according to KCNA, that “the challenges faced by us for the past several months were harsh and dangerous, which others would not withstand even a single day but give up, but no difficulties can ever stop or delay the rush of our people advancing as an integral whole, undaunted by whatever hardships.”“This means,” Kim added before the speech marking the 75th anniversary of the communist nation’s founding, “a great victory, and our possession of promising strategic weapon system planned by the Party.”

North Korea had expressed increasing frustration with the U.S. since President Donald Trump walked out of their last formal summit in February. Kim resumed missile launches at a record-setting pace and repeatedly warned that his two-year freeze on Intercontinental ballistic missile and nuclear-bomb tests might be coming to an end.

“In the future, the more the U.S. stalls for time and hesitates in the settlement of the DPRK-U.S. relations, the more helpless it will find itself before the might of the Democratic People’s Republic of Korea,” Kim boasted.

Even as 2019 drew to a close, Kim was huddled behind closed doors with the ruling Workers’ Party in Pyongyang for one of the most significant such meetings since he took power eight years ago. He urged the so-called plenum “to take positive and offensive measures for fully ensuring the sovereignty and security of the country as required by the present situation,” KCNA said on Monday.

‘Fell in Love’

While Trump in 2018 claimed that North Korea was “no longer a nuclear threat” and that he and Kim “fell in love,” a deal between the two countries has remained elusive.

Neither side can agree on the terms of disarmament or U.S.-imposed economic sanctions. Meanwhile, North Korea has continued to conduct missile tests and build its nuclear arsenal.

North Korea had suggested a “Christmas gift” would be forthcoming after demanding additional concessions as part of the stalled nuclear talks. Earlier this year, Kim’s regime set a Dec. 31 deadline for a breakthrough. Trump has downplayed any threat, saying on Christmas Eve that the U.S. will “deal with it” and joking that Kim’s “gift” could be a “beautiful vase.”

Robert O’Brien, Trump’s national security adviser, said this month that the U.S. will be ready to respond should Kim fire additional long-range missiles or conduct further nuclear weapons tests.

“We’ll reserve judgment, but the United States will take action as we do in these situations,” O’Brien said on ABC’s “This Week.” “If Kim Jong Un takes that approach, we’ll be extraordinarily disappointed and we’ll demonstrate that disappointment.”

To contact the reporter on this story: John Harney in Washington at jharney2@bloomberg.net

To contact the editors responsible for this story: Michael Shepard at mshepard7@bloomberg.net, John Harney, Larry Liebert

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