North Korean leader Kim Jong Un pledged during his visit this week to Beijing to achieve "results" that would be welcomed by the international community at his potential next summit with U.S. President Donald Trump, China's state-run media said Thursday.

In a meeting with Chinese President Xi Jinping on Tuesday, Kim also reiterated that North Korea will stick to its goal of denuclearization of the Korean Peninsula, according to the reports.

The two leaders agreed that Beijing and Pyongyang would work together to resolve issues related to the divided peninsula, with Xi expressing clear support for North Korea's efforts to hold summit meetings with Washington, Xinhua News Agency said.

Kim, whose visit came at a time of stalemate in denuclearization negotiations with Washington, explained to Xi the "challenges and concerns" that have arisen in the process of those talks, North Korea's official Korean Central News Agency said.

China is North Korea's major economic and political ally and this year marks the 70th anniversary of the establishment of diplomatic relations between them.

Kim invited Xi to make an official visit to North Korea "at a convenient time" and the latter gladly accepted the offer, KCNA reported.

In his New Year's address on Jan. 1, Kim said, "I am ready to meet the U.S. president again anytime," promising not to make nuclear weapons in the future.

Kim, however, warned that North Korea may seek a "new path" if Washington maintains pressure on Pyongyang, indicating that it might return to a policy of pursuing weapons of mass destruction.

Xi told Kim that China hopes the United States and North Korea "will move forward together," according to the Chinese media.

(A car believed to be carrying North Korean leader Kim Jong Un drives toward Beijing station on Jan. 9, 2019.)

China will "play a positive and constructive role" in realizing denuclearization of the Korean Peninsula, Xi was also quoted as telling Kim by Xinhua.

Xi's remarks suggest that Beijing, which has been engaged in a tit-for-tat tariff war with Washington, will use North Korea as a bargaining chip in future trade negotiations with Trump by being actively involved in denuclearization talks, some analysts say.

Speculation is rife that Trump and Kim will hold their second meeting early this year. In the wake of the latest agreement with China, North Korea is likely to accelerate preparations for the summit with the United States, diplomatic sources in Beijing said.

South Korean President Moon Jae In, who has voiced eagerness to serve as a broker between Washington and Pyongyang, said at a press conference on Thursday that Kim's trip to China is "a strong sign" that the next U.S.-North Korea summit is drawing near.

The North Korean leader was accompanied to China by Kim Yong Chol, who has led negotiations with the United States, and Foreign Minister Ri Yong Ho, KCNA reported.

At their historic meeting in Singapore in June 2018, Kim and Trump agreed that Washington would provide security guarantees to Pyongyang in exchange for its "complete denuclearization."

But negotiations between the United States and North Korea have been at an impasse against a backdrop of the Trump administration's skepticism about Kim's intention to give up nuclear weapons.

North Korea has called on the United States to ease economic sanctions aimed at preventing Pyongyang from developing ballistic missiles and nuclear weapons, saying it has already started to take concrete measures toward denuclearization of the Korean Peninsula.

China has supported North Korea's position, with Kim recently committing to put more emphasis on revitalizing his nation's economy, which is considered to be sluggish due largely to the sanctions, than on strengthening its nuclear capacities.

At their meeting in Beijing, the Chinese and North Korean leaders also discussed economic cooperation between the two countries.

Kim told Xi that he was "deeply impressed by the achievements made in China's economic and social development" and that he "hopes for more trips to China for study and exchanges," Xinhua said.

In April, the ruling Workers' Party of Korea, led by Kim, vowed to concentrate more on building a "powerful socialist economy."

Beijing "firmly supports" the new strategic line that focuses on "developing economy and improving people's well-being," Xi was quoted by the Chinese news agency as telling Kim.

China and North Korea fought together in the 1950-1953 Korean War against U.S.-led United Nations forces. The two countries have been described as "blood brothers." Washington and Pyongyang have no diplomatic ties and remain technically at war.

Kim arrived in Beijing by train on Tuesday, widely believed to be his birthday, marking his fourth trip to China as North Korea's leader. The visit was at the invitation of Xi.

On Wednesday morning, Kim visited an economic development zone in southern Beijing, which houses many high-tech companies. Later in the day, he left Beijing station by train to return to North Korea.

In March last year, Kim traveled to Beijing in his first foreign trip since becoming North Korea's supreme leader following the death of his father Kim Jong Il in late 2011. During 2018, he visited China a total of three times to hold talks with Xi.