BEIJING/SEOUL-- A special envoy of Chinese President Xi Jinping arrived in North Korea Friday, a report said, amid apparent strains between the two communist allies due to Pyongyang's recent nuclear and missile provocations.

In a report from Pyongyang, Japan's Kyodo News said the Chinese Envoy, Song Tao, met with Choe Ryong-hae, a vice chairman of the North's ruling Workers' Party, shortly after his arrival in Pyongyang.

Song and about four other Chinese officials were earlier seen at a Beijing airport with North Korean ambassador in Beijing Ji Jae-ryong seeing them off.

Song's trip to the North comes after the recent conclusion of the Chinese Communist Party Congress. Seoul officials noted Beijing has traditionally sent a ranking official to its communist ally to explain the outcome of its party congress. Song currently heads the international relations department at the Central Committee of the Communist Party.

However, his trip also follows Xi's bilateral summit with U.S. President Donald Trump in Beijing last Thursday. During his 12-day tour of Asia, which included visits to Japan and South Korea, the U.S. president called on China to do more to rein in North Korea's evolving nuclear and missile programs.

Details about Song's itinerary have not been unveiled, but diplomatic sources said that he may make a four-day visit to the North, during which he could meet with North Korean leader Kim.

Seoul's unification ministry said that China's special envoys dispatched to the North after the party congresses in 2007 and 2012 met with former North Korean ruler Kim Jong-il and the current leader, respectively.

China's foreign ministry said that the two sides will exchange views on issues of mutual interest at the party and country level, and that Song will report on the outcome of China's party congress.

Experts say that the issue of North Korea's nuclear and missile programs is likely to be discussed at a time when Pyongyang has suspended its provocative acts for more than 60 days.

Joseph Yun, the top U.S. nuclear envoy, reportedly said at a recent meeting that if North Korea halts nuclear and missile testing for about 60 days, that would be the signal Washington needs to resume direct dialogue with Pyongyang.

Yun was in South Korea's southern Jeju Island to have talks over North Korea's nuclear issue with his South Korean counterpart Lee Do-hoon.

The U.S. envoy said he hopes Song's trip would help "forward" the goal of its denuclearization.

Lee also added that it could have "a very significant meaning considering the current situation."

Yun said in Seoul on Tuesday that he does not know the reason for North Korea's halting of provocations, but he called on the North to stay that course "for a period of time."

Meanwhile, North Korea's main newspaper said Friday that the country will not put issues directly linked to its core interests and its people's security on the negotiation table.

"The United States should abandon its hostile policy toward North Korea. If Washington does not give it up, we will not budge by an inch from the path to strengthening our nuclear force," said the Rodong Sinmun, the mouthpiece of the ruling Workers' Party of Korea.

Source: Yonhap News Agency