"This proposal has been sent to all the embassies in Pyongyang," Lavrov said. "We are now trying to clarify the situation. We asked our North Korean neighbors a few questions that need to be asked in this situation."
About two dozen countries have embassies in North Korea. Lavrov said during a visit to Uzbekistan as saying that Russia is in touch with China, the United States, Japan and South Korea — all members of a dormant talks process with North Korea — to try to figure out the motivation behind the warning.
"We are very much worried by inciting of tensions, even though it's verbal so far," Lavrov said. "We would like to understand the reasons behind the proposal to evacuate the embassies, whether it's a decision of the North Korean leadership or a proposal. We were told it's a proposal."
North Korea's government did not comment on the embassy warnings. Tensions have been roiling in the past few weeks following a North Korean nuclear test and the country's subsequent warnings to South Korea and the United States that it would be prepared to attack.
Britain's Foreign Office confirmed that it had received the warning, which it called part of ongoing rhetoric from Pyongyang to portray the U.S. as a threat.
"The British Embassy in Pyongyang received a communication from the North Korean government this morning saying that the North Korean government would be unable to guarantee the safety of embassies and international organizations in the country in the event of conflict from April 10th," it said in a statement.
Britain said it was "considering next steps" and had no immediate plans to withdraw from Pyongyang.
Sweden said North Korea's foreign ministry had a meeting with foreign diplomats but didn't order them to leave.
"It was a meeting that dealt with the security situation in the country, where the North Koreans asked whether there was any need for assistance in case of an evacuation," Swedish Foreign Ministry spokesman Teo Zetterman said.
Sweden also represents the United States, which doesn't have an embassy or any direct diplomatic presence in North Korea. Any Americans in North Korea would be NGO workers or tourists but it's not officially known how many might be there.
"This is just an escalating series of rhetorical statements, and the question is, to what end?" U.S. State Department spokeswoman Victoria Nuland told reporters in Washington.
"This is an unpredictable regime and an unpredictable situation," Nuland said. "Our posture remains to be prudent, to take appropriate measures, in the defense and deterrence sphere, both for ourselves and for our allies, but to continue to urge the DPRK to change course, because this is not going to end their isolation."
The U.S. Embassy in Seoul also issued a notice to Americans in South Korea, saying it had "no specific information to suggest an imminent threat to U.S. citizens or facilities."
The U.N. says its staff was continuing to work in North Korea while Secretary-General Ban Ki-moon studied the North Korean message to consider evacuating U.N. personnel.
U.N. spokesman Martin Nesirky said a U.N. representative joined diplomats at a meeting Friday in Pyongyang and that U.N. staff "remain engaged in their humanitarian and developmental work throughout the country."
Asked whether Ban would go to Pyongyang, Nesirky said the U.N. chief has offered to facilitate dialogue "to help to bring people together."
"Dialogue is what's needed to try to turn the volume down. The volume has been turned up tremendously high in recent days and the volume needs to be turned back down again and the secretary-general is certainly keen to help," he said.
Nesirky added that the U.N. was "providing very important life-saving assistance to people, particularly children" in North Korea.
Russia has appeared increasingly upset with North Korea, strongly criticizing its neighbor for its "defiant neglect" of U.N. Security Council resolutions.
"We are counting on maximum restraint and composure from all sides," a Russian foreign ministry statement said Friday.
Other nations with diplomatic missions in North Korea, such as the Czech Republic, Romania, Poland, Bulgaria and India, also said they were weighing the situation carefully. The Czechs said they had no plans to withdraw; the Romanians and Bulgarians were speaking with the 27-nation European Union about the situation.
"Naturally, we assess that there is no outside threat to North Korea whatsoever," said Marcin Bosacki, spokesman for Poland's Foreign Ministry. "In our opinion, the current military rhetoric is exclusively directed to the internal audience and does not reflect the true international intentions of the country."