Two summits between Kim and Xi have seen the leaders reaffirm the countries' long-standing ties, as well as agree to continue high-level meetings.
In an unusual move, Chinese state media announced Kim's visit and said he would stay for two days.
"No matter the changes in the global and regional situation, China's party and government's resolute position on being dedicated to consolidating and developing Sino-North Korea relations will not change", the report cited Xi as saying.
Trump's comments come in the wake of a summit in Singapore with Kim Jong Un that Trump has cast as dramatically reducing the nuclear threat posed by North Korea despite no specific commitments about how it will eliminate its weapons.
While not formally billed as a state visit, China gave Kim most of the trappings of one, including a welcome ceremony with honor guard in Beijing's Great Hall of the People. Kim first traveled to China to meet with Chinese President Xi Jinping in March in Beijing and again in May in Dalian.
The North Korean leader touched down on Tuesday morning with reporters spotting Kim's $1 million armored Mercedes at the airport before a motorcade entered Beijing's streets.
Kim Jong-un's latest trip to China has also sparked speculations that sanctions imposed by Beijing may be discussed.
Kim is expected to be received by Xi in Beijing. But on Tuesday the USA and South Korean militaries confirmed they have called off a major joint exercise following Trump's order.
Hagin is a huge loss to the Trump administration after serving in every GOP White House since the Reagan era. By publicly sharing the details of Kim's global trip, China has granted North Korea more legitimacy, furthering its desire to be treated like any other country.
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Prime Minister Shinzo Abe told reporters the government was "working united, with its first priority on saving people's lives". Railway services in Osaka, Shiga, Kyoto and Nara, both high speed bullet trains and local rail services, were halted.
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The West Indian said the huge defeat has made the players realise where they stand in the five-day format. All is certainly not lost, for no team has begun its journey in Test cricket being the finished product.
A trade war with the US could make it less attractive for China to use its influence over North Korea to help the USA achieve its objectives of denuclearization.
"The biggest concern of course is whether China [would] be excluded".
On his part, Xi said that he "wants North Korea and the USA to carry out the results of their leadership summit" in Singapore, the report said.
Or maybe China has its own reasons for making Kim's presence in Beijing known immediately. To do that, he needs the Chinese to make such gestures. Trump wrote on Sunday.
The two-day exercise - tiny compared with the suspended US-South Korea war games - will involve six warships and seven aircraft and had begun, Seoul's defence ministry said.
"I believe that indicates that the blood alliance between the North and China has been completely restored", Yang said. Along the Chinese border, Radio Free Asia reports officials are now only checking around half the vehicles that pass through, while a short time ago x-ray scans were being done on every vehicle.
"If the two parties can solidly implement the summit's consensus step by step, it will open a new, important phase of the denuclearisation of the Korean Peninsula".
Critics also oppose the president's decision to end major joint military exercises without getting any major concession in return from North Korea.
Trump recently ordered tariffs on $50 billion in Chinese goods in retaliation for alleged intellectual property theft.