North Korea appears to be trying to bolster ties with its friendly neighbor China with the coronavirus pandemic taking a severe toll on the country's economy, while its nuclear talks with the United States have shown no sign of progress.

Two years have passed since the first-ever U.S.-North Korea summit took place on June 12, 2018, in Singapore, but denuclearization negotiations between their leaders have remained stalled after their meeting broke down over sanctions relief in Hanoi early last year.

As political unrest is expected to grow in the United States ahead of the November presidential election, Pyongyang, which has long sought the easing of economic sanctions, has been finding it difficult to resume talks with Washington, diplomatic sources said.

(Chinese President Xi Jinping (L) and North Korean leader Kim Jong Un in Pyongyang on June 21, 2019)[KCNA/Kyodo]

Under the circumstances, North Korean leader Kim Jong Un has become more frustrated with the South's President Moon Jae In, who has called himself a "broker" between Pyongyang and Washington but so far failed to make achievements in nuclear negotiations, they said.

"In economic terms, China is the most important country for North Korea, which has been forced to rebuild its economy hit hard by the virus outbreak. Kim's top priority is now to bring North Korea's trade with China back to normal," one of the sources said.

"On the other hand, Kim may take a wait-and-see attitude toward the United States before the end of the presidential election, while stepping up provocations against South Korea to maintain his grip on power at home," he said.

"The virus epidemic and the U.S. presidential race have ended up making Kim more eager to deepen relations with China," he said, adding regardless of whether President Donald Trump will be re-elected or not, Beijing's influence on Pyongyang "would increase further."

In the wake of the spread of the new coronavirus that causes the respiratory disease COVID-19, North Korea has cut off traffic to and from China since earlier this year, although Pyongyang has claimed it has seen no infections in the country.

Related coverage:

North Korea vows to develop chemical sector for self-sufficient economy

N. Korea vows to abolish joint liaison office with South: KCNA

China warns U.S. spreading "political virus" vilifying China

As trade with China has become stagnant, North Korea's economy, which already languished due largely to international sanctions aimed at thwarting its nuclear and ballistic missile ambitions, has faced a serious downturn, foreign affairs experts say.

North Korea depends on China, its closest and most influential ally, for over 90 percent of its trade.

Recently, Pyongyang has aggressively expressed its support for China's controversial issues including its determination to impose a national security law on Hong Kong, designed to crack down on what Beijing views as subversive activity in the territory.

Late last month, North Korea's Foreign Ministry spokesperson was quoted by the state-run Korean Central News Agency as saying, "Hong Kong is an inseparable territory where the sovereignty of the People's Republic of China is exercised and its Constitution is applied."

"We fully support the measures taken by the (Communist) Party and government of China for safeguarding the sovereignty, security and territorial integrity of the country," the spokesperson said.

When U.S. Secretary of State Mike Pompeo on May 31 accused the Chinese Communist Party of being "intent upon the destruction of Western ideas, Western democracies, Western values," a spokesman of North Korea's ruling Workers' Party defended Beijing days later.

"Pompeo ought not to have such a pipe dream of undermining the Communist Party and socialism on their long victorious drive as what the successive rulers of the U.S. dreamt," the spokesman said in a statement carried by KCNA on June 4.

(A signboard calling for friendly ties between China and North Korea, written in the languages of both countries, is seen in Pyongyang on June 20, 2019, as Chinese President Xi Jinping arrives for talks with North Korea's leader Kim Jong Un)

"It is very clear that North Korea has cast amorous glances at China," another diplomatic source in Beijing said.

Pyongyang, meanwhile, has begun to take a hardline stance against Seoul, as North Korean watchers have speculated that Kim may be worried that the economic deterioration stemming from the virus pandemic would erode his political clout in the country.

North Korea pledged Tuesday to shut down all lines of communication with the South in protest at defectors launching balloons over the border containing leaflets lambasting Pyongyang. It has indicated that it would even scrap an inter-Korean military pact.

As Kim's sister and close aide Kim Yo Jong has started to supervise policies toward the South, "North Korea would not give an inch against the South," the source in Beijing said.

On Thursday, Kwon Jong Gun, director general of the Department of U.S. Affairs of North Korea's Foreign Ministry, also urged the United States not to meddle in inter-Korean affairs, warning that otherwise, it may "encounter an unpleasant thing."

"How can the 'disappointment' touted by the U.S. be compared with the extreme dismay and resentment we are feeling at the U.S. and the south Korean authorities that have repeated betrayal and provocation for the last two years?," Kwon said, according to KCNA.

In a statement released Friday through the news agency, Foreign Minister Ri Son Gwon said North Korea is "to build up more reliable force to cope with the long-term military threats from the U.S."

A diplomat familiar with the situation in Pyongyang said, "As Sino-U.S. tensions have been escalating over several matters like trade and Hong Kong, North Korea has taken a golden opportunity to get closer to China."

"North Korea's moves could continue to promote a decoupling in the region," he said.

As for Japan, one of the closest security allies of the United States in East Asia, which has been at odds with Pyongyang over the long-standing issue of past abductions of its nationals by North Korean agents, Kim Jong Un has been little interested in holding bilateral talks.

"Kim has seen Japan as a U.S. client state. He is unlikely to extend an olive branch to Tokyo unless U.S.-North Korea negotiations go forward," the diplomat said.