WASHINGTON -- As Secretary of State Mike Pompeo prepares to travel this week to North Korea, experts cautioned that the Trump administration’s plan to dismantle the North’s nuclear weapons and missiles in a year is both unrealistic and risky.

The State Department said Pompeo would arrive Friday on his third visit to Pyongyang in three months. It will be the first visit by a senior US official since President Donald Trump’s historic meeting with Kim Jong-un on June 12 in Singapore, where the North Korean leader committed to "complete denuclearization" of the Korean Peninsula.

Trump’s questionable claim afterward that the North was no longer a nuclear threat was soon displaced by doubts about how to achieve denuclearization, a goal that has eluded US administrations for the past quarter-century since Pyongyang began producing fissile material for bombs.

The president tweeted Tuesday that talks on the next steps with North Korea are "going well" and claimed his efforts had defused any nuclear threat.

”If not for me, we would now be at War with North Korea!’’ Trump tweeted. He said: "No Rocket Launches or Nuclear Testing in 8 months. All of Asia is thrilled."

But experts say there is no proof North Korea’s halt of nuclear and missile tests means the North will take concrete steps to give up such weapons. They also say the US has an unrealistic approach to North Korea’s denuclearization.

Less than three weeks ago, Pompeo said the United States wanted North Korea to take "major" nuclear disarmament steps within the next two years -- before the end of Trump’s first term in January 2021. Even that was viewed as bullish by nonproliferation experts considering the scale of North Korea’s weapons program and its history of evasion and reluctance to allow verification of disarmament agreements.

On Sunday, Trump’s national security adviser, John Bolton, publicized the more ambitious one-year plan that he said Pompeo will be discussing with the North Koreans. Bolton, who has expressed hardline views on North Korea, said that if Pyongyang has decided to give up its nuclear weapons program and is cooperative, then "we can move very quickly" and they can win sanctions relief and aid from South Korea and Japan.

The rapid timeline he proposed contrasts with more measured, methodical strategies that most North Korea experts insist are needed to produce a lasting denuclearization agreement. They say any solid deal will require Kim to be completely transparent about his program -- at a time when intelligence reports suggest he will try to deceive the United States about the extent of his covert weapons or facilities.

The one-year plan is predicated on the North Koreans "rolling over and playing dead," said Joel Wit, a former State Department official who helped negotiate a 1994 agreement that temporarily froze Pyongyang’s nuclear program. "If it’s our going-in position, it’s fine. We should give it a try and see where it goes. If it’s our bottom line, it’s dead on arrival and then provides a pretext for John Bolton to make mischief."

To date, Kim has halted nuclear and missile tests and has destroyed tunnels at the North’s nuclear test site, but the authoritarian nation has yet to take concrete steps toward abandoning its weapons programs. Recent think tank analyses using satellite imagery suggest that Pyongyang may even be expanding some facilities linked to its missile and nuclear programs.

The Washington Post on Saturday cited unnamed US intelligence officials as concluding that North Korea does not intend to fully surrender its nuclear stockpile. Evidence collected since the summit points to preparations to deceive the US about the number of nuclear warheads in North Korea’s arsenal as well as the existence of undisclosed facilities used to make fissile material for nuclear bombs, according to the report. Some aspects of the updated intelligence were reported Friday by NBC News.

A US official told the Associated Press that the Post’s report was accurate and that the assessment reflected the consistent view across US government agencies for the past several weeks. The official was not authorized to comment publicly on the matter and spoke on condition of anonymity. 

North Korea and Washington have yet to negotiate the terms under which the North would relinquish its weapons, so Pyongyang can be expected to seek leverage in those discussions. But those reported activities could add to misgivings in the United States, which has seen agreements with the North flounder before, often amid allegations of evasion or cheating. Pyongyang has often had its own complaints about Washington over slow delivery of aid and imposition of sanctions.

"Denuclearization is no simple task. There is no precedent for a country that has openly tested nuclear weapons and developed a nuclear arsenal and infrastructure as substantial as the one in North Korea to give up its nuclear weapons," Daryl Kimball, executive director of the Arms Control Association, wrote in a commentary published Monday.

A strategy by David Albright at the Institute for Science and International Security suggests the US needs to get Kim to disclose a complete list of all his nuclear program sites and materials, including uranium and plutonium. He also said Trump and Kim should decide whether to move the nuclear weapons out of North Korea to dismantle them or do it inside the country. 

Even if North Korea is cooperative, the magnitude of dismantling its weapons of mass destruction programs, believed to encompass dozens of sites, will be tough, according to Stanford University academics, including nuclear physicist Siegfried Hecker, a leading expert on the North’s nuclear program.

The Stanford team has proposed a 10-year roadmap, based on its belief that "North Korea will not give up its weapons and its weapons program until its security can be assured." (AP)