China has an obligation to prevent the export to North Korea of items banned under UN Security Council resolutions, a senior White House official said, following revelations that a Chinese conglomerate has shipped to the North "dual-use" items that can be used in its weapons programs.

Earlier this week, joint research by South Korea's Asan Institute and the US Center for Advanced Defense Studies found that China's Liaoning Hongxiang Group exported aluminum oxide, which can be used in uranium enrichment, to the North in recent years.

The research findings also showed that the Chinese trading firm has been selling other "dual-use" items, such as aluminum ingots, ammonium paratungstate and tungsten trioxide, all of which can be used in the North's missile or nuclear programs.

"China has an obligation to implement fully the sanctions that have been passed at the UN Security Council, including preventing the export to North Korea of a variety of goods and technologies," White House Deputy National Security Adviser Ben Rhodes said, though he said he's not familiar with the allegations involving the Chinese conglomerate.

"When we see concerns about that we do raise them directly with China," he told reporters late Tuesday.

On Wednesday, Jon Wolfsthal, senior director for arms control and nonproliferation at the White House's National Security Council, also said that UN resolutions clearly ban the exports of any items that can be used for its nuclear and missile programs "even if it's a pencil."

"It doesn't matter if it's a pencil or an ounce of gold or a boatload of coal," Wolfsthal said in response to a suggestion that the aluminum oxide that the Chinese conglomerate exported to the North is not enough to help build nuclear weapons.

"Everything that North Korea does we believe is linked or supportive of their weapons of mass destruction program and that trade is to be prohibited unless it can be demonstrated conclusively that it is to support humanitarian purposes," he told reporters after a Wilson Center seminar.

The official declined to discuss the specific case involving the Chinese firm, including whether or when the US Treasury Department provided related information to China and when the US

is expected to take legal action against the firm.

Rhodes said that the US hopes to see China fully implement UN sanctions and discuss with Beijing "appropriate responses to this cycle of provocations, which could include additional sanctions."

"We want China to understand that in the long run it is going to be less secure if we see this pattern of provocation out of North Korea, both because of the instability of having a nation like North Korea pursuing a nuclear program and a ballistic missile program, but also, frankly, because there are things that China objects to like our deployment of the THAAD missile defense system," he said.

Obama discussed these issues when he held talks with Chinese Premier Li Keqiang earlier this week, Rhodes said.

"I think China has grown more serious, they've taken steps that they've never taken before in terms of the previous UN Security Council resolution and the nature of their condemnations of North Korea's actions. But we want to continue to see follow-up from them," he said.

Wolfsthal said the US and China are working hard on a new UN sanctions resolution.

"It's something that even through the UN General Assembly process, we're engaged in very concertedly very attentively. It's something that it's a top priority for the president and our entire administration because of the priority we view addressing the North Korean nuclear threat," he said.

The official said, however, it's difficult to say when a draft resolution will be put together. He also said the US will not "let the clock dictate whether or not we get a good or better resolution" because the goal is to increase the pressure and improve the sanctions regime on the North.

"China is in agreement with us that what we've tried in the past has not worked, that improved sanctions, implementation and expansion is the only way we will convince North Korea to return to negotiating table," the official said.

"If sanctions' aren't increased, North Korea will only become bolder and the United States and its allies will have to take increased military steps which China also views as a challenge and something that we think can be avoided if we can get firm implementation of sanctions in the near term," he said. (Yonhap)