According to the statement, Pyongyang claimed the reason for the test was the country's right for "self-defense," and promised not to use nuclear weapons if the international community respects its sovereignty.
Pyongyang also said that it was ready to continue with actively developing its military industry and nuclear weapon in case of possible threats.
North Korea state TV celebrating the announcement of the h-bomb test. pic.twitter.com/TKvPGS3bKA— Breaking News Feed (@pzf) January 6, 2016
Earlier, South Korea claimed that North Korea might have conducted a nuclear test on Wednesday, which caused an earthquake in the country.
South Korea's weather service reported that the earthquake was of an "artificial nature."
The USGS say that the earthquake was of 5.1 magnitude with the epicenter located in Pekam county, in Yangkang province.
South Korean sources reported that the earthquake occurred near the town of Kilchu.
North Korea says the nuclear test was a hydrogen bomb and that it was a success pic.twitter.com/ya97elIEGG— Anna Fifield (@annafifield) January 6, 2016
South Korean intelligence claims that North Korea did not notify the United States and China about their plans to conduct a nuclear test, the Yonhap agency reports, citing a representative of South Korean intelligence service.
In 2003, Pyongyang withdrew from the international Nuclear Non-Proliferation Treaty (NPT), a deal that was intended to prevent the spread of nuclear weapons manufacture and possible use.
In 2005, North Korea declared itself a nuclear power, and conducted several nuclear weapons tests, sparking concerns in the international community, particularly in neighboring South Korea. Almost four years later, Pyongyang tested additional nuclear weapons.
The official data on the country's nuclear program has not been released, and research on the issue is based on external observations and reports made by North Korean authorities.
In December, North Korean leader Kim Jong Un said the country had a hydrogen bomb and was ready to use it to "protect its sovereignty and national dignity."