North Korea did not carry out any ballistic missile or nuclear test in 2018 for the first time in seven years, underscoring Pyongyang's seriousness about putting more emphasis on economic improvement than on arms development.

Although the outlook for its denuclearization negotiations with the United States remains uncertain, North Korea is likely to accelerate diplomatic efforts in 2019 in a bid to obtain security guarantees from Washington, foreign affairs experts say.

Until the end of 2017, Pyongyang launched 55 ballistic missiles and conducted nuclear tests four times since 2012, one year after Kim Jong Un became North Korea's supreme leader in the wake of the death of his father Kim Jong Il, according to the Japanese Defense Ministry.

On Nov. 29, 2017, North Korea fired what it said was its "most powerful" intercontinental ballistic missile capable of delivering a nuclear warhead to anywhere in the United States, with Kim Jong Un declaring the completion of "the state nuclear force."

Fears of a potential military clash escalated, but the situation turned around in 2018. Kim surprisingly extended an olive branch to South Korea in his address on Jan. 1 and later in the year pledged to achieve "complete denuclearization" on the Korean Peninsula.

In March, Kim visited Beijing in his first foreign trip since becoming the supreme leader. During 2018, he held talks with Chinese President Xi Jinping and South Korean President Moon Jae In three times, respectively, and met U.S. President Donald Trump.

North Korea's relations with China -- Pyongyang's main economic lifeline -- and the South markedly improved in 2018.

Kim and Trump, meanwhile, agreed at the first-ever U.S.-North Korea summit in Singapore on June 12 that Washington will provide security guarantees to Pyongyang in return for complete denuclearization of the divided peninsula.

Since then, negotiations between the United States and North Korea have been mired in a stalemate due to Trump's skepticism about Kim's intention to abandon nuclear weapons, but Kyodo News has witnessed a change in the atmosphere in Pyongyang this year.

On the 106th anniversary of the birth of North Korea's late founder Kim Il Sung on April 15, called the "Day of the Sun," political slogans in public spaces in Pyongyang made no mention of the country's ballistic missile and nuclear weapons programs.

At an annual exhibition featuring around 24,000 roots of "Kimilsungia," a purple flower of the orchid family named after Kim Il Sung, there were no replicas of satellite-carrying rockets or missiles, unlike on previous anniversaries.

When a group of Kyodo News journalists visited Pyongyang again in July, locals said the number of foreign travelers to North Korea had drastically increased since the first inter-Korean summit in 11 years on April 27 in the truce village of Panmunjeom.

Okryu-gwan -- which offered Pyongyang's traditional delicacy of cold noodles to Kim Jong Un and Moon at their summit dinner -- and other sightseeing spots, including a cruising restaurant, a zoo and historical sites, have been flourishing, the locals said.

On July 28, Kyodo News reporters confirmed that around 350 out of the total 384 guests on the day of a luxury restaurant ship on Taedong -- a major river that runs through the heart of the capital -- were people from other nations.

In April, North Korea promised to "concentrate all efforts on building a powerful socialist economy," while vowing to discontinue nuclear and ICBM tests.

"The tourism is one of the key industries for North Korea to invigorate its economy," which has been sluggish amid international economic sanctions aimed at preventing Pyongyang's development of nuclear weapons and missiles, a diplomatic source in Beijing said.

As part of celebrations marking the 70th anniversary of North Korea's founding on Sept. 9, Pyongyang staged a military parade but did not display ICBMs, signaling Kim's desire to refrain from provoking Trump for the sake of promoting denuclearization talks.

On the same day, the country's first "Mass Games" in five years featured state-of-the-art technologies like drones and projection mapping. At the torch march the following day, tens of thousands of North Korean youths formed such slogans as "Economic Construction."

Pyongyang's consolatory overtures have also appeared in its media coverage.

By the night of Dec. 27, North Korean media reported Kim's public activities 132 times and 64, or 48.5 percent, of them were relevant to diplomacy, said Radio Press news agency, which analyzes overseas broadcasts.

The number of military-related news reports was a record low of eight, or 6.1 percent, of the total, whereas they accounted for about 40 to 50 percent for the five years through 2017, the Tokyo-based news agency said.

[Photo courtesy of Korea Media]

In 2019, Kim is rumored to make a trip to Seoul for the first time as North Korea's leader to meet with Moon and hold a second summit with Trump.

Xi is also expected to visit North Korea as 2019 marks the 70th anniversary of the establishment of diplomatic ties between Beijing and Pyongyang.

"If North Korea restarts ballistic missile or nuclear tests, it would really prompt Trump to take military action," another diplomatic source in Beijing said.

"North Korea understands it. I think North Korea will continue to try not to irritate the United States, while still trying to get backing from China and South Korea," he added.