The US government says it believes China has provided help for North Korea’s missile programme.
Reports have suggested a missile transporting vehicle seen at a Pyongyang military parade resembled others of Chinese design.
At a Washington hearing, US Defence Secretary Leon Panetta was asked whether Beijing had supported North Korea’s missile programme via “trade and technology exchanges”.
“I’m sure there’s been some help coming from China. I don’t know, you know, the exact extent of that. I think we’d have to deal with it in another context in terms of the sensitivity of that information. But clearly there’s been assistance along those lines,” he replied.
China and other countries are banned under two UN Security Council resolutions from helping North Korea with its ballistic missile programme.
Beijing has denied breaking any rules.
Pyongyang has rejected Western criticism of last Friday’s failed rocket launch, vowing to continue putting satellites into space for peaceful purposes.
The US believes it was a long-range missile test.