Pyongyang's state media reported that Kim on Saturday told the powerful Central Committee of the ruling Workers' Party the nuclear weapons were a "powerful deterrent" guaranteeing the country's sovereignty against what he described as "protracted nuclear threats of the U.S. imperialists," VOA reported.

But he acknowledged that North Korea's standoff with the United States, Japan, South Korea and other countries over its nuclear weapons development was a "complicated international situation."

Kim vowed to continue developing the country's economy as it advanced North Korea's weapons program in the face of stiffened United Nations sanctions aimed at curbing Pyongyang's export income. He said North Korea faces "ordeals" under a "stern" situation but claimed its economy has grown.

Kim tightened his family's firm grip on the government, promoting his sister, Kim Yo Jong, to be an alternate member of the politburo, the top decision-making body over which Kim Jong Un presides.

Kim's support for North Korea's nuclear weapons program came as Trump said Saturday that "only one thing will work" in dealing with North Korea after previous U.S. administrations had negotiated with Pyongyang without results.

Read alsoNorth Korea preparing for new missile provocations – media"Presidents and their administrations have been talking to North Korea for 25 years, agreements made and massive amounts of money paid," Trump said in a Twitter comment. "Hasn't worked, agreements violated before the ink was dry, making fools of U.S. negotiators. Sorry, but only one thing will work!"

It was not clear exactly what Trump meant, but seemed to suggest that he was referring to military action. Trump has engaged in weeks of taunts with Kim, saying the United States would "totally destroy" North Korea if necessary to protect itself and its allies if Pyongyang attacks. North Korea has conducted numerous missile and nuclear tests.

Abe, at the outset of campaigning for Japan's October 22 national election, said Sunday he would impose "all possible pressure" on North Korea over its missile and weapons development. Pyongyang has launched some missile tests over Japan.

"We need to create a situation in which North Korea wants talks as it will change policy," Abe said at a political debate. "We will protect our country under stable politics."