It was a warm overture from the North Korean leader, who rarely issues personal messages, as China is being urged by the international community to do more to rein in the North's missile and nuclear tests that have raised tensions globally.
"It expressed the conviction that the relations between the two parties and the two countries would develop in the interests of the peoples of the two countries," the North's state-run central news agency said in a statement, citing the message sent by Kim to Xi.
"The Chinese people have entered the road of building socialism with the Chinese characteristics in the new era" under the guidance of Xi, the message also said.
The letter came just a day after China wrapped up its week-long conclave which unveiled a new leadership line-up without naming a clear successor.
China is the North's sole major ally, and accounts for more than 90 percent of trade with the isolated country.
China has said it will strictly enforce UN Security Council sanctions banning imports of coal, textiles and seafood, while cutting off oil shipments to the North.
(Reporting by Christine Kim; Editing by Sandra Maler)
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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