A security threat to the United States will increase if the country ignores a year-end deadline set by North Korea, a senior official warned, according to a statement carried Monday by the official Korean Central News Agency in English.

Kim Yong Chol, chairman of the Korea Asia-Pacific Peace Committee, was also quoted by the news agency as saying leader Kim Jong Un may have different views on its nuclear talks with the United States if President Donald Trump continues to make provocative remarks against Pyongyang.

"If the U.S. has no will and wisdom, it cannot but watch with anxiety the reality in which the threat to its security increases with the passage of time," Kim Yong Chol said.

(North Korea's "super-large multiple rocket launchers" test-fired on Oct. 31, 2019.)[Korean Central News Agency/Kyodo]

The statement came a day after North Korea said Sunday that it has conducted a "very important test" at a rocket launch site, which some foreign affairs experts believe was a liquid-fuel engine test for a long-range ballistic missile launch.

With few signs that the two nations will make concessions over denuclearization, tensions between them have been rekindled, with Trump hinting at using U.S. military might against North Korea if necessary.

Recently, North Korea has said that it will resume nuclear and intercontinental ballistic missile tests if the negotiations fail to attain a breakthrough by the end of the year.

On Sunday, Trump said in Twitter posts, "Kim Jong Un is too smart and has far too much to lose, everything actually, if he acts in a hostile way. He signed a strong Denuclearization Agreement with me in Singapore."

"He does not want to void his special relationship with the President of the United States or interfere...with the U.S. Presidential Election in November," Trump added.

Responding to Trump's tweets, Kim Yong Chol said that the U.S. president -- who has been eager to secure diplomatic achievements in the run-up to next year's presidential race -- is an "old man bereft of patience."

"As he is such a heedless and erratic old man, the time when we cannot but call him a 'dotard' again may come," Kim Yong Chol said.

Criticizing Trump for having a lack of understanding toward Korea, Kim Yong Chol said, "We have nothing more to lose," indicating that Pyongyang will take whatever steps are possible, including a launch of an ICBM, capable of reaching the United States.

Later Monday, Ri Su Yong, a vice chairman of the ruling Workers' Party of Korea, via KCNA, released another English statement lambasting Trump.

"Trump might be in great jitters but he had better accept the status quo that as he sowed, so he should reap, and think twice if he does not want to see bigger catastrophic consequences," Ri said.

"Our final judgment and decision which will soon be made at the end of this year are to be done" by Kim Jong Un, Ri added.

At the first-ever U.S.-North Korea summit in June 2018 in Singapore, Trump promised to provide security guarantees to Pyongyang in return for "complete" denuclearization of the Korean Peninsula.

North Korea, however, has claimed that Washington has not implemented the agreement despite Pyongyang taking, what it says are, concrete measures to discard its nuclear arsenal.

Since earlier this year, North Korea has carried out test-firings of what appeared to be short-range ballistic missiles in defiance of U.N. Security Council resolutions banning Pyongyang from developing ballistic missiles and nuclear weapons.

North Korea, meanwhile, has said it will discuss and decide on "crucial issues" at a key ruling party meeting later this month in line with "the changed situation at home and abroad."

Washington and Pyongyang technically remain in a state of war after the 1950-1953 Korean War ended in a cease-fire. The two nations do not have diplomatic relations.