"If the objective of the visit is to improve North Korea-China ties through a summit between the two leaders of the nations, then there is no reason to carry out the first formal meeting in such secrecy" said Cha Du-hyeogn, a researcher at the Asan Institute for Policy Studies, while raising the possibility of the North Korean leader's sister Kim Yo-jong being the mystery North Korean visitor to Beijing.
South Korea's presidential office said it could not confirm reports that the train carried Kim nor a separate report that Kim's sister was onboard.
Footage of the train from the Tokyo-based Nippon News Network showed a green carriage with yellow horizontal lines.
"If we have information, we will publish it", Hua said, while adding that China was willing to work with North Korea to "continue to play a positive and constructive role in order to realise the denuclearisation of the peninsula".
The trip is suspected to be Kim's first known overseas trip since coming to power in 2011, after his father and predecessor Kim Jong-il's death.
There were reports a train belonging to the Kim family had arrived in the Chinese capital with the rumors being reinforced by the large security presence outside the Diaoyutai State Guesthouse, where previous North Korean leaders had stayed in the past.
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The move comes several days after Trump added a new lawyer to the team, former United States attorney Joseph diGenova. China responded in kind on Friday, announcing proposed tariffs on 128 USA products worth close to $3 billion.
The unannounced visit followed a flurry of diplomacy that saw North Korea's participation in the Winter Olympics in Pyeongchang last month.
Such a trip would be seen as a potential precursor to Kim's planned summit with South Korean President Moon Jae-in in late April and his anticipated meeting with Trump by May.
North Korea's relations with China, a traditional ally, is believed to have soured in recent years with China's support of worldwide sanctions against North Korea chief among a number of points of conflict.
"If the U.S. -North Korea summit goes well, then sanctions on North Korea would be eased, but if negotiations fail, then sanctions on the regime may be strengthened".
China has been largely sidelined by the developments between the two Koreas and the United States, although it has repeatedly given public backing for talks between Washington and the Koreas.
"North Korea wants to have some insurance against this upcoming summit meeting with President Trump ... the meeting is very important but also very risky", he said.
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The action and reaction fit a Trump White House pattern of declining to chide authoritarian regimes for undemocratic practices. Administration officials said it was unclear if the President had seen the briefing memo that was leaked to the Post.
But they also expressed doubts over whether Kim would visit China in such a "secretive" manner. Analysts, however, questioned whether Kim would make the visit to Beijing himself rather than send an envoy.
"Numerous other senior officials could and would have taken a private plane, possibly departing without any fanfare in Pyongyang and arranging to establish an unobtrusive arrival with the Chinese authorities", Madden said.
The South Korean government also said it couldn't confirm whether the North Korean leader was in Beijing.
At the same time, Beijing fears the collapse of the regime in Pyongyang and the instability it would bring, potentially sending waves of refugees into China and the possibility of U.S. troops stationed on its border in a unified Korea.
White House spokesman Raj Shah said the United States could not confirm reports of Kim's visit to China, but instead reiterated President Donald Trump's plans to meet with Kim.
"They're concerned about being left out, with the North Koreans directly cutting a deal with the Americans that doesn't necessarily reflect Chinese interests", Bishop told AFP.
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The government would spend Rs 5 lakh for school managing committees to strengthen libraries, arts and education. The Budget also mentions the creation of a Road Safety Policy draft and a road safety fund to be created soon.