0133 GMT July 18, 2019
Xi, who will be the first Chinese president to visit Pyongyang in 14 years, penned a rare front-page opinion piece in North Korea's official newspaper, touting their "irreplaceable" bond on the eve of this two-day trip, AFP reported.
Xi is visiting the country on today and Friday at the invitation of North Korean leader Kim Jong-un as both men face their own protracted negotiations with US President Donald Trump.
With his visit, Xi can show that China still has some influence on its Cold War-era ally and play a role in efforts to convince Pyongyang to abandon its nuclear program.
It could also give the Chinese leader some leverage when he meets Trump to discuss the US-China trade war at the G20 next week in Japan.
For Kim, having his powerful next-door neighbor visit will serve as a reminder to Trump that Xi will have his back if the nuclear talks fail for good.
In the opinion piece in the Rodong Sinmun, Xi said Beijing was willing to draw up a "grand plan" with Pyongyang to achieve permanent stability in East Asia.
He also vowed that Beijing would play an active role in "strengthening communication and coordination with North Korea and other relevant parties" to push forward negotiations on the Korean Peninsula.
At subway stations in Pyongyang, commuters crowded around newsstands to read Xi's article.
It appeared on page one of the Rodong Sinmun, in the bottom right-hand corner.
The trip by the leader of the North's key diplomatic ally and main provider of trade and aid has long been awaited, and comes after Kim traveled to China four times for meetings with Xi.
China and North Korea have worked to improve relations in the past year from a low point as Beijing backed a series of UN sanctions against its Cold War-era ally over its nuclear activities.
Russia and China on Tuesday blocked an American initiative that aimed to halt fuel deliveries to North Korea, which Washington accuses of exceeding its annual limit for 2019, diplomatic sources said.
Hu Jintao was the last Chinese president to visit Pyongyang in 2005, when he met Kim's father, Kim Jong-il.
Xi, who will be given the honor of a state visit, will pay homage at the capital's Friendship Tower.
In his op-ed, Xi stressed that this year marks the 70th anniversary of Beijing-Pyongyang relations.
"Over the past 70 years we have been unyieldingly advancing forward in the same boat, breaking through rain and wind," Xi wrote.
"One can say this friendship is irreplaceable, even with an enormous fortune."