China Thursday called for restraint and efforts to ease tensions after North Korea claimed it has made nuclear warheads small enough to mount on missiles.
  

China's foreign ministry spokesman Hong Lei made the remarks a day after North Korea's powerful National Defense Commission made the claim, saying the country's "nuclear striking means have entered the stage of producing smaller nukes and diversifying them."
  

"We have taken note of such reports," Hong replied, when asked about the North's claim about its advance in weapons technology.
 

"China consistently stands for the denuclearization of the Korean Peninsula, peace and stability of the Korean Peninsula, and settlement of relevant issues through dialogue and consultation," Hong said.
  

"Currently, the Korean Peninsula has witnessed a sensitive and complex situation," Hong said. "China urges the parties concerned to exercise restraint, avoid provoking each other, do more to ease tensions, and resume the six-party talks at an early date."
  

In Washington, Patrick Ventrell, a spokesman for the White House's National Security Council, dismissed the North's claim, saying, "Our assessment of North Korea's nuclear capabilities has not changed. We do not think that they have that capacity."
  

North Korea's claims on its advance in nuclear and missile technology always have been met by skeptical responses, but Pyongyang, which has conducted three nuclear tests, put an object into an orbit in late 2012.
  

The six-party talks aimed at resolving the North Korean standoff have been stalled since late 2008. (Yonhap)