Kim Jong-un, a mysterious motorcade, and a potentially historic trip to China 

Shaky mobile phone footage of a motorcade zooming through the streets of Beijing deepened the intrigue on Tuesday surrounding whether a groundbreaking meeting had taken place between North Korea’s Kim Jong-un and Chinese leaders.

The motorbike convoy was just one of many clues for amateur detectives, who have this week been scrambling to piece together fragments of information about who is in town and why.

After a dark green armoured train was spotted rolling through Beijing’s suburbs on Monday, the motorcade was later seen heading towards a location where Xi Jinping, the Chinese president, typically hosts foreign dignitaries.

Adding to the mystery, Beijing’s already stringent security was notably heightened.

Streets were blocked off by armed guards and police in hi-visability jackets, and Kim-watchers were given further ammunition as Chinese censors cracked down on mentions of Mr Kim and the reported visit from the internet.

The unusual activity all served to boost speculation that Mr Kim was making a secretive visit to the Chinese capital ahead of anticipated talks with Donald Trump, the US president.

"North Korea likely wants to confirm its relationship with China and believes it has some leverage with which it can ask for things from China," Yoo Ho-yeol, professor of North Korean studies at Seoul’s Korea University, told Reuters.

If it was Mr Kim on the train – similar to the one his father used for his final Chinese trip in 2011 – it would mark the first foreign visit by the young North Korean leader and show that the hermit state is keen to shore up relations with its neighbour.

Nearly two days after Japanese media initially reported a high-level North Korean official was visiting the capital, it was still unclear who the special attention was for.

The green train was seen leaving Beijing station on Tuesday afternoon. China remained tight-lipped on whether there had been a visit.

Questions about whether the trip had concluded after just one day were met with a terse statement from a foreign ministry spokesman, who said: "If there is news, we will release it."

Mr Kim’s name, "North Korea" and also "Kim Fatty the Third" – the name which Chinese web users use to ridicule the rotund leader – were all restricted on social media.

Even phrases that riffed on the nickname – such as "Fatty Fatty Fatty has come" and "Fatty Fatty Fatty Beijing" – also appeared to have been banned from Sina Weibo, the Chinese equivalent of Twitter.

The convoy entered Beijing’s Diaoyutai State Guest House on Monday night, and departed the compound just before 11am local time on Tuesday morning.

Local security and the paramilitary police stood guard as unidentified men in plainclothes attempted to prevent photographers from taking pictures.

Reports emerged of tourists being moved away from Tiananmen Square, near the Great Hall of the People, on Monday.

Chinese leaders also often welcome foreign guests in the cavernous Mao-era building, leading sleuths to question whether Mr Kim was being given a tour.

The timing of Mr Kim’s visit – if he was indeed visiting – is fortuitous.

He has a summit with Moon Jae-in, the South Korean president, scheduled for late April, and the much-touted meeting with the US president in May.

“At a possibly historic moment, before the start of a dramatic play on the Korean Peninsula, China was losing the spotlight,” said Cheng Xiaohe, a North Korea expert at Beijing’s Renmin University told the the Washington Post, adding that the visit would boost Beijing’s standing.

After relationships thawed following the Pyeongchang Winter Olympics earlier this year, Mr Kim will attend an historic summit with South Korean leaders next month to resolve the stand-off over the North’s advancing nuclear programme.

Zhang Liangui, a professor of international strategic research and an adviser on North Korean policy to the Chinese government, told The Daily Telegraph: "The US has pledged to seek a solution to this problem through the use of force if necessary, which makes it urgent for Kim to adjust his policy.

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"I think he may have come to China to show he has changed his attitude."    

Past visits by Mr Kim’s father, Kim Jong-il, were surrounded in secrecy, with Beijing only confirming his presence after he had crossed the border by train back into North Korea.

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