Russian newspaper Pravda Report claims 25% of the city's residents have been told to flee.

According to South Korean media, residents in the hermit kingdom have said goodbye to each other sparking concerns tyrannical Kim Jong-un could be about to act after months of nuclear weapon testing.

The latest rumours come after North Korean officials announced a "big and important event" tomorrow.

Foreign reporters have been told to prepare for the event on North Korea's biggest national celebration called "Day of the Sun".

(Image: TWITTER)

Around 200 foreign journalists are in Pyongyang as the country marks the 105th birth anniversary of its founding president Kim Il Sung on April 15.

Donald Trump and Jong-un continue to bash heads as war fears grow between the two nations.

Officials in North Korea have warned nuclear war could break out at any minute thanks to the "extremely tense" situation on the Korean Peninsula.

America sent a US Navy strike group towards the Western Pacific in a show of force, while North Korea warned it would launch a nuke attack in response to any act of aggression.

And China moved 150,000 soldiers close to the North Korea border in preparation for war.

(Image: GETTY)

It comes after Trump launched 59 Tomahawk missile to blast a Syrian airfield in response for the country's brutal chemical attack which killed 79 civilians.

North Korean officials gave no details about the nature of the surprise event or where it would take place, but in the past similar announcement have turned out to be relatively low-key.

They told foreign journalists in Pyongyang invited to mark the national holiday that their schedule had been cancelled, and to instead meet early on Thursday to prepare for a "big and important event".

In 2016 foreign journalists underwent hours of investigation by North Korean officials ahead of what turned out to be a pop concert to mark the finale of a ruling Workers' Party congress.

But on the 100th day of the Sun in April 2012, North Korea attempted to launch a long-range rocket.

With war tensions raging, some are wondering whether Kim will use the special date to strike America after months of threats over nuclear weapons.

Chinese President Xi Jinping called for a peaceful resolution to the North Korean problem in a telephone conversation with Trump today.

Security experts recently warned Kim could be planning an underwater nuclear attack using a secret submarine.

In the past North Korea's submarines have been able to disappear and avoid detection, with up to 50 vanishing off the radar in 2015.

Security expert Bruce Klingner told CNBC: “We didn't know where they were at the time. One would hope that we would keep very close tabs on those that could launch the submarine-launched ballistic missiles [SLBMs].

“All of that is very worrisome because that may very well have a nuclear weapon someday.”