The tubby tyrant is thought to have planned the launch of a nuclear device for April 15, in honour of his forebear Kim il-Sung, who founded North Korea in 1948.
Kim Il-Sung, also known as the Eternal President of the Republic, died 23 years ago before handing the Hermit Kingdom over to his son Kim Jong-il.
And activity at the Punggye-ri nuclear test site in North Korea has caused concerns among observers that the rotund ruler may be looking to celebrate his predecessor’s birthday with a bang.
A Beijing-based diplomat said: "It concerns me that the North is doing excavation work at two tunnels (of the site).
It comes tensions between the dictator and US President Donald Trump reach fever pitch
"Lots of analysis and evaluation will be needed to determine whether both of them, when completed, will be used to conduct nuclear tests simultaneously or at a short interval and what nuclear materials will be used."
"There are chances that the North will conduct an additional nuclear test, though I cannot say for sure that it will come around the summit between the U.S. and China (in early April) or Kim Il-sung's birthday (on April 15).
"It could be done around April 25 when it celebrates the anniversary of the Korean People's Army."
It comes tensions between the dictator and US President Donald Trump reach fever pitch, with the Kim regime threatening to reduce the US to “ashes” over their military buildup in the southern region.
Secret images released as North Korea prepares for war Tue, March 21, 2017
A look at North Korea's firepower as it pursues its nuclear and ballistic missile programs in defiance of the United States and its allies.
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People watch news footage of a missile launch on a giant television screen outside the main railway station in Pyongyang on March 7, 2017
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North Korea have been ramping up their missile capabilities
In a threatening statement, the North Korean government said: “The Korean People's Army will reduce the bases of aggression and provocation to ashes with its invincible Hwasong rockets tipped with nuclear warheads and reliably defend the security of the country and its people's happiness in case the US and the South Korean puppet forces fire even a single bullet at the territory of the DPRK.”
Mr Trump meanwhile claimed Kim was “acting very, very badly” while members of his government claimed they were ready to challenge the isolated nation’s “ever escalating threat”.
Trump’s Secretary of State Rex Tillerson said it was astounding the US government had provided over £1billion in aid to North Korea with no improvement in the region.
Kim Il-Sung, also known as the Eternal President of the Republic, died 23 years ago
Mr Trump meanwhile claimed Kim was 'acting very, very badly'
He said two decades of expensive diplomatic efforts has failed to achieve the goal of denuclearising Pyongyang and something needed to be done before it was too late.
He said: “So we have 20 years of failed approach. That includes a period where the United States has provided $1.35billion (£1.1billion) in assistance to North Korea as an encouragement to take a different pathway.
"In the face of this ever-escalating threat, it is clear that a different approach is required.”