Trump reportedly canceled Pompeo's trip to North Korea after it sent a mysterious and hostile letter

Shealah Craighead/White House

President Donald Trump received a letter from North Korean Leader Kim Jung Un on June 1, 2018, by North Korean envoy Kim Yong Chol.

• President Donald Trump reportedly called off Secretary of State Mike Pompeo's trip to North Korea after reportedly receiving a mysterious and hostile letter from Kim Jong Un's government. 
• Officials declined to comment on the contents of the message and how it was transmitted.
• On Monday, North Korea's state newspaper accused the US of plotting to "unleash a war" on Pyongyang while continuing to negotiate "with a smile on its face."

President Donald Trump reportedly called off Secretary of State Mike Pompeo's trip to North Korea after reportedly receiving a mysterious and hostile letter from Kim Jong Un's government. 

Senior officials in the Trump administration told The Washington Post, Pompeo received the letter from Kim Yong Chol, vice chairman of North Korea's ruling Workers' Party Central Committee, on Friday morning, and showed it to Trump. Officials declined to explain how the letter was transmitted.

While the contents of the message are unclear, it was reportedly hostile enough for Trump to nix Pompeo's travels and issue a series of tweets. 

"Secretary Pompeo looks forward to going to North Korea in the near future, most likely after our Trading relationship with China is resolved. In the meantime I would like to send my warmest regards and respect to Chairman Kim. I look forward to seeing him soon!" Trump tweeted.

Press Secretary Sarah Huckabee Sanders told CNN on Saturday that Pompeo was in the room when Trump sent out the tweets.

On Monday, North Korea's state newspaper responded to Pompeo's abrupt cancelation and accused the US of plotting to "unleash a war" on Pyongyang while continuing to negotiate "with a smile on its face."

Sunday's Rodong Sinmun newspaper, the official mouthpiece of the ruling Worker's Party of Korea, called out "extremely provocative and dangerous" US military movements in the region, and claimed that US "special units" in Japan staged a flying drill in the Philippines simulating "the infiltration into Pyongyang."

It also claimed that the USS Michigan, a nuclear Navy submarine, transported Green Berets and other special forces from Okinawa, Japan to the Jinhae naval base south Korea in late July or early August.

Relations between North Korea and the US hit a roadblock after the US asked North Korea to reveal its secret nuclear facilities, and which it claimed not to have.

Meanwhile, satellite imagrey of the country suggests that North Korea may actually be continuing or increasing its production of nuclear material.