Xi is also expected to attend the G20 summit in Osaka, Japan, next week, but Beijing has yet to confirm whether the Chinese leader will meet US President Donald Trump.

Ko Min-jung, a spokeswoman for the South Korean presidential office, said Xi’s trip to North Korea would promote “the peaceful resolution of the Korean peninsula issue”.

“I hope that this visit will contribute to the early resumption of talks on the complete denuclearisation of and the establishment of permanent peace on the Korean peninsula,” Ko said.

But, she added, there was no plan for Xi to visit South Korea before or after the G20 summit.

By highlighting Beijing’s influence over Pyongyang, Xi’s trip is expected to increase China’s diplomatic leverage on the North Korean nuclear front and strengthen its hand in dealing with the United States.

Zhang Liangui, a specialist in North Korea at the Central Party School in Beijing, said that Xi’s visit had great geopolitical significance.

“Diplomatically, Xi’s visit to Pyongyang is a reciprocal trip given that Kim Jong-un has paid four visits to China since March 2018,” Zhang said.

“But considering the current international situation and especially the escalating trade war between Beijing and Washington, the trip is obviously an important geopolitical move.

“In the lead-up to the meeting between Xi and Trump at the G20, both sides are trying to find a way out. Apart from the trade tensions, they will also touch on other important bilateral and regional issues, with defusing tensions on North Korea high on their agenda.”

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Zhang called North Korea one of the few issues in which Beijing and Washington had common interests.

“Discussions over North Korea could help showcase their efforts to set aside their differences. Xi’s trip [to North Korea] will allow Beijing to continue to play an important role in Korean peninsula affairs,” he said.

“It’s also quite natural for Xi to visit Pyongyang now as Washington is communicating with South Korea over the issue, including Trump’s possible visit to Seoul before or after G20.”

But Beijing needed to be careful about making promises to North Korea about relaxing United Nations sanctions, one of Kim’s top priorities, Zhang said.

“While it’s all right for China to provide some food and medical assistance out of humanitarian concern, China should abide by the existing UN sanctions regime and refuse to go further.

“One of the main lessons we’ve learned from the failure to block Pyongyang’s nuclear ambitions is that North Korea will not voluntarily denuclearise and we must not pin our hopes solely on diplomacy, negotiations, or even compensating Pyongyang for sanctions.”

Zhang Baohui, director of the Centre for Asian Pacific Studies at Lingnan University in Hong Kong, said that Xi might use the issue to both pressure and broker a deal between Washington and Pyongyang.

“It is difficult to guess Beijing’s real intention but either way it would only increase China’s diplomatic leverage in the Korean issue and its [influence] over the US,” Zhang Baohui said.

“If Xi persuades Kim [to denuclearise], this would ultimately give China more bargaining power vis-a-vis the US during the denuclearisation process … After all, China-North Korea relations have a tremendous impact on China-US relations.”

Boo Seung-chan, adjunct professor at the Yonsei Institute for North Korean Studies in Seoul, said Xi was cleverly using North Korea as a diplomatic card ahead of his expected meeting with Trump next week.

“China may be using North Korea as leverage amid its trade conflicts with the US,” Boo said.

“Xi might want to strengthen Beijing’s position as a messenger – or a mediator – to accelerate the denuclearisation process ahead of his meeting with Trump so he will have some diplomatic cards to play [in dealing with] Trump.

“I don’t see this as pressuring the US, however, rather than sending Washington a message that they, too, need China in the denuclearisation process.”

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The last time a Chinese president visited North Korea was in 2005, when Hu Jintao made a three-day trip and was hosted by Kim’s father, Kim Jong-il.

The trip comes as the two countries prepare to mark the 70th anniversary of the establishment of diplomatic ties.

It also follows a warming in China’s relations with North Korea and stalled nuclear talks between Pyongyang and Washington. North Korea said in December that it would not give up nuclear weapons unless the US reduced its military presence in South Korea.