Today, a Foreign Office spokesman reportedly said: “We can confirm that the British Embassy in Pyongyang received a communication from the North Korean government this morning.
“It said that the North Korean government would be unable to guarantee the safety of embassies and international organisations in the country in the event of conflict from April 10.”
The Foreign Office today confirmed that it has “no immediate plans to withdraw our embassy” in Pyongyang and said it condemned the “provocation” by the North Korean government.
A spokesman went on: “The Democratic People’s Republic of Korea has responsibilities under the Vienna convention to protect diplomatic missions, and we believe they have taken this step as part of their continuing rhetoric that the US poses a threat to them.”
The Foreign office declined to disclose how many staff are working in Pyongyang, but said no decision had yet been taken on whether to pull out. "We are considering next steps," the spokesman added.
Troops ... South Korean female army reservists raise their hands to adopt a resolution against North Korea
Pledge ... South Korea is currently
engaged in joint military exercises with the US
Two rockets have been loaded onto mobile launchers and hidden in special underground facilities on North Korea's east coast , according to a government official.
The official added: “The North is apparently intent on firing the missiles without prior warning.”
The range of the second missile is unknown though it is believed to be an inter-continental ballistic KN-08 missile, which is untested by the regime.
It came as a powerful 6.2 magnitude earthquake struck near the North Korean border in far-eastern Russia.
The epicenter of the quake, which struck at 1pm (GMT) was south-west of Vladivostok, around five miles from Russian border town Zarubino.
Meanwhile, the Pentagon has pledged to tone down pronouncements about its military build-up after the crisis on the Korean peninsula threatens to spiral out of control.
In recent days, the US has flown two B-2 stealth bombers over South Korean and announced an expansion of missile defence systems in Alaska and Guam.
But rather than encouraging North Korea to back down, the US's military movements have prompted even greater threats and belligerent rhetoric from Pyongyang.
PYONGYANG move sees South Korea deploy two warships with missile-defence systems
Drills ... South Korean soldiers prepare
to fire a howitzer during a military exercise
On US official said: “Our actions thus far have had their intended effect: they've shown our deterrence capability and our willingness to defend South Korea.
“We always make adjustment and if going quiet for a short period of time gives the North Koreans space to dial back their rhetoric, fine.”
However, Washington still plans to forge ahead with joint military exercises with Seoul – including an amphibious assault drill – branded by the North as “rehearsal for invasion”.
The exercises codenamed Foal Eagle began on March 1 and will end on April 30.
Some US analysts expressed alarm over the intensity of the North’s threats. Centre for Strategic Studies senior adviser Victor Cha said: “The rhetoric is off the charts.”
But despite the North's threats to attack the US, David Cameron was today slammed for making the extraordinary claim yesterday that North Korea could strike Britain.
Young ... a South Korean soldier stands on a
military guard post near the demilitarised zone
Experts disputed his comments, saying North Korea does not have missiles that can reach Europe nor can mount nuclear warheads on them, sparking comparisons with the “sexed-up” dossier which Tony Blair used to justify the invasion of Iraq ten years ago.
The significance of next Wednesday is unclear, although it has also been mentioned as a date for the possible closure of the Kaesong Industrial Complex, a facility inside the North where South Korean companies employ 53,000 people.
The foreign ministry on Friday gave ambassadors in Pyongyang until Wednesday to say if they needed help with closing their missions and evacuating staff.
Britainresponded by saying there was "no immediate" plan to shut its embassy in North Korea.
On Friday North Korea released a video of Kim Jong-Un firing a handgun
Kim Jong-un, the North Korean leader, has sparked a regional crisis by testing a nuclear weapon and then revoking the armistice with South Korea and threatening immediate attack.
In response to tighter United Nations sanctions and annual US-South Korean military exercises, Mr Kim has gone so far as to "authorise" a nuclear strike on America. Washington has responded by bolstering its defences around the Pacific Island base of Guam and sending nuclear-capable B2 bombers over the Korean Peninsula.
But a Foreign Office spokesman made clear that Britain had not decided to close its embassy. London established diplomatic relations with North Korea in 2001, opening an embassy in Pyongyang which concentrates on nuclear proliferation and human rights. Michael Gifford, the current British ambassador, remains in North Korea.
Britain had not interpreted the communication from North Korea as a recommendation to leave, said the Foreign Office. The regime was simply pointing out that it "would be unable to guarantee the safety of Embassies and international organisations" in the "event of conflict".
There were more signs of escalation on Friday. The North Korean foreign ministry declared the question was "not whether, but when a war would break out" owing to the "increasing threat from the United States", according to Xinhua, the official Chinese news agency.
North Korea is understood to have moved a second long range missile to its east coast, which has been the location for previous test launches. The weapons are believed to be "Musudans", an untested model with a possible range of 2,000 to 2,500 miles - theoretically enough to strike Japan and Guam.
South Korea countered by deploying two destroyers equipped with the Aegis missile defence system. One warship will patrol the country's east coast and the other will protect the west, tasked with shooting down any hostile North Korean missiles.
Aegis is a sophisticated system combining radars with projectiles capable of destroying a missile in-flight. At a minimum, the warships would be able to track any North Korean missile launches and establish whether they are harmless test firings - or acts of war. "If the North fires off a missile, we will trace its trajectory," an official told Yonhap, the South Korean news agency.
However, Gen Martin Dempsey, the chairman of the US joint chiefs of staff, said that North Korea's behaviour followed a familiar pattern of provocation and was unlikely to lead to war. Any such conflict would pit North Korea against the US, guaranteeing Mr Kim's defeat.
A Cuban Army anti-aircraft battery during the 1962 missile crisis (Reuters)
As tensions rise, Mr Kim has stepped up his personal security, perhaps in fear of a military coup, a Japanese newspaper, Chosun Ilbo, reported. In particular, about 100 armoured vehicles have been deployed close to Mr Kim's official residence in Pyongyang, said the paper, quoting diplomatic sources.
"The situation inside North Korea is very unstable and the military are making a lot of complaints to their political leaders," said Toshimitsu Shigemura, an expert on North Korea at Wasaeda University in Tokyo. "The military needs tension with South Korea and the US to justify themselves and Kim is terrified of a coup."