North Korea has created miniature nuclear warheads which can be mounted on ballistic missiles, the country's leader Kim Jong Un has announced.
According to the North's KCNA news agency, he made the announcement which inspecting nuclear workers, saying it was a "true nuclear deterrent".
North Korea has been slapped with severe sanctions after carrying out a fourth nuclear test in January.
It has claimed it was a successful hydrogen bomb test, but this has been been disputed by a number of experts as well as the governments of South Korea and the United States.
North Korea's leader ordered his country's nuclear weapons to be readied for use at a moment's notice according to official state media.Read the full story ›
Launch of short-range missiles today appears to be in retaliation to new sanctions imposed by the UN Security Council.Read the full story ›
Sanctions against North Korea could be dramatically expanded in response to its nuclear test on January 6, as the UN Security Council plans to vote on new measures later today.
According to the US mission to the United Nations, the vote is expected at 8pm UK time.
The US presented a draft resolution it had negotiated with China to the 15-nation council last week, proposing to significantly tighten restrictions after North Korea carried out a nuclear test and rocket launch.
If passed, it would create the toughest UN sanctions regime in two decades, they said.
An American student detained in North Korea since the start of the year has confessed to "severe crimes" against the state, according to state media.
University of Virginia student Otto Warmbier, aged 21, was taken into custody before boarding his flight to China after an unspecified incident at his hotel, his tour agency told Reuters in January.
State media in Pyongyang quoted him as saying: "I committed the crime of taking out a political slogan from the staff-only area of the Yanggakdo International Hotel."
North Korea has a history of detaining foreign visitors, and both the US and Canadian governments advise against travelling there.
Japan's Foreign Minister Fumio Kishida has called for stronger sanctions to be placed on North Korean after the isolated nation launched a long-range rocket at the weekend.
The United Nations has condemned the launch at an emergency meeting and vowed to take "significant measures" in response to the violation of UN resolutions.
The UN Security Council has strongly condemned North Korea's rocket launch.
The Security Council has reiterated its intent to take "significant measures" in response to the nuclear test in January, it said in a statement.
"The members of the Security Council strongly condemned this launch," Venezuelan Ambassador Rafael Dario Ramirez Carreno, president of the council this month, told reporters.
He said the launch was "a serious violation of Security Council resolutions."
U.S. Ambassador Samantha Power told reporters: "We will ensure that the Security Council imposes serious consequences. DPRK's (North Korea) latest transgressions require our response to be even firmer."
The United States and China began discussing a U.N. sanctions resolution after Pyongyang's Jan. 6 atomic test.
The foreign secretary has said the North Korean missile test is a "slap in the face" for the UN and the international community.
Philip Hammond said: "North Korea's actions are extremely destabilising in the region and beyond."
Hammond said he had spoken to the Japanese foreign minister this morning and they are looking into economic sanctions that could be applied against North Korea, but it does require agreement across the UN security council.
Whatever the North Koreans say we are clear that this missile test involves prohibited ballistic missile technology that is subject to restricted United Nations resolutions.
The fact that the North Koreans have carried out this test today is a slap in the face for the UN and the international community.
The Foreign Secretary has condemned North Korea's "ballistic missile technology test" saying the country's actions were "a threat to regional and international security".
Philip Hammond will attend an emergency meeting with UN Security Council members to agree a collective response.
I strongly condemn North Korea's ballistic missile technology test. This is a clear and deliberate violation of a number of UN Security Council Resolutions. North Korea's actions continue to present a threat to regional and international security.
In conducting this provocation, North Korea has clearly demonstrated that it is intent on prioritising the development of its nuclear and ballistic missile programmes over improving the well-being of its own people.
As North Korea is aware, the UN Security Council unanimously agreed to take significant measures against any further launches or nuclear tests. We will now meet with our partners in New York to agree a collective response.
Russia has condemned North Korea's launch of a long-range missile calling it a serious blow to security in the region
"It is obvious that such actions lead to a serious aggravation of the situation on the Korean peninsula and Northeast Asia on the whole...(and) inflict serious damage to the security of the countries of the region, first and foremost North Korea itself," the foreign ministry said in a statement.
The ministry urged the leadership of North Korea to "think about whether a policy of opposing the entire international community meets the interests of the country."