There are growing calls for the Group of Eight (G8) to send a strong, united message to North Korea.
G8 foreign ministers are set to meet tomorrow in London to discuss tensions on the Korean peninsula, as well as the situation in Syria and Iran.
German Foreign Minister Guido Westerwelle on Tuesday called on the regime in Pyongyang to put an end to its saber-rattling.
"We urge them that they de-escalate, that they understand that this war rhetoric has to end," he said.
Japanese Foreign Minister Fumio Kishida, who met with his German counterpart in the Netherlands, called for the G8 to take stern action.
"Concerning North Korea and their series of acts - such as launching of missiles, conducting nuclear tests and also uttering provocative words - constitute a serious provocation to not only our country and neighboring countries, but to the international community as a whole,'' said Japan's foreign minister.
"In the face of such words and deeds by North Korea, we as government of Japan, we will first endeavor to gather information and analyze that information and make thorough preparations for any unexpected or unforeseen contingencies, so that we can establish measures to ensure and protect safety and security of our citizens," he added.
Meanwhile, a Russian Foreign Ministry spokesman told the state-run RIA news agency Moscow shares those concerns and rejects what it called North Korea's "provocative and bellicose line of conduct."
The G8 brings together the United States, Britain, Russia, Japan, Canada, France, Germany and Italy.
North Korea's rhetoric also prompted warnings from United Nations Secretary-General Ban Ki-moon, in Rome for a meeting with Pope Francis.
"If any small incident caused by miscalculation or misjudgment, it may create an uncontrollable situation," said the U.N. chief. "That is why I have been urging the DRPK [Democratic People's Republic of Korea] authorities to refrain from this provocative rhetoric and I have been urging the countries concerned in and around the Korean peninsula to exercise their influences to North Korea.''
There is also growing concern on the part of China, where officials are keeping a watchful eye on the country's border with North Korea.
Chinese Foreign Ministry spokesman Hong Lei said Beijing does not want to see "war or chaos" on its doorstep. He said, "We believe that the situation on the Korean peninsula at present is very complex and sensitive. China opposes any side taking actions to worsen tensions and opposes any side doing anything to harm peace and stability on the peninsula.''
The G8 foreign ministers meeting is expected to wrap up on Thursday.
U.S. Secretary of State John Kerry said he also plans to meet with members of the Syrian opposition during the two-day conference.