North Korea does not appear to have miniaturized nuclear warheads to fit on its ballistic missiles despite having advanced its technology to "a considerable level," Seoul's defense ministry said Thursday.
  

Officials and experts from South Korea and the United States have said the communist country is believed to have the technology to build nuclear-tipped missiles, though Pyongyang has yet to demonstrate the miniaturization capability.
  

"Despite its significant technology level, we don't think the North is capable of making such nuclear weapons," ministry spokesman Kim Min-seok said at a regular press briefing.
  

Touching on an analysis by U.S. expert Joel Wit that Pyongyang is currently believed to have 10-16 nuclear weapons -- six to eight of them based on plutonium and four to eight based on weapons-grade uranium, Kim said it is "simply a presumption without any evidence."
  

Asked about the expected timing of the North's next nuclear test, Kim said, "No such signs have been detected."
  

Earlier in the day, South Korea's daily Segye Times reported that the communist country has prepared to carry out the fourth detonation test in May, citing government sources.
  

"As we've repeatedly said, North Korea seems to be fully prepared for a test whenever it wants. But it should be determined to face a significant level of political pressure, such as sanctions from the United Nations," Kim said.
  

North Korea has conducted three rounds of nuclear tests so far -- in 2006, 2009 and 2013. Last year, it threatened to conduct a "new form" of nuclear test, repeatedly vowing to develop its economy and nuclear arsenal in tandem. (Yonhap)