The meeting between top North Korean diplomat Ri Su Yong and Xi caught North Korea watchers by surprise.
On paper, China is North Korea's closest and most powerful ally but it's is no secret that relations between Beijing and Pyongyang have been at a low point in recent years.
North Korea has continued to push ahead with its nuclear weapons and missile programs
; ignoring China's calls for restraint. Pyongyang's latest nuclear test in February this year
, was particularly needling for Beijing.
Xi's travel schedule seemed to indicate that North Korea and its young leader Kim Jong Un had fallen out of favor.
In 2014, President Xi traveled to North Korea's arch enemy South Korea and again met the South's president Park Geun-Hye in Beijing in 2015. He has never met North Korea's supreme leader Kim Jong Un.
Much of the world sees China as the only country with the means to force North Korea to curb its nuclear ambitions.
And China, previously considered to have been lax in implementing UN sanctions against North Korea, appears to be enforcing the current round quite thoroughly.
Pyongyang, however, has said that it will not give into pressure, and will continue its current course whatever the economic cost.
Message from Kim Jong Un
According to official media reports, the Workers' Party of Korea delegation headed by Ri Su Yong, delivered a message from North Korea's supreme leader Kim Jong Un.
It expressed "the hope to strengthen and develop bilateral friendship and to maintain peace and stability in the region. "
Ri also reaffirmed that North Korea would continue its 'two front lines policy" of developing nuclear weaponry in tandem with reinvigorating its isolated and stagnating economy.
Xi, in turn, called on all relevant sides to stay calm, exercise restraint and enhance communication and dialog to safeguard regional peace and security.
Xinhua, China's official news agency gave few details, but the landmark meeting can be interpreted as a slight thawing in the frosty relations between historical and ideological friends.
North Korea knows that China's cooperation is essential if it is to carry out the economic side of its 'two front' policy -- China is its biggest international trading partner and a major supplier of aid.
By receiving the North Korean delegation in Beijing, like the emperors of old receiving visits from tributary states, China is demonstrating to Pyongyang its senior status, with the power to grant or deny.
But with the Shangri-La Dialogue, Asia's biggest security summit starting this weekend in Singapore, Beijing is also sending a message to the U.S. and South Korea that, despite misgivings, it is not abandoning its old ally and all parties are going to have to get used to that.