National Security Advisor John Bolton on Thursday called on China to exert pressure on North Korea, as the road ahead for denuclearization talks remains unclear.

“China could really hold the key to this here if they press North Korea hard enough,” he said during an exclusive interview with Breitbart News’ Editor-in-Chief Alex Marlow on Sirius XM’s Breitbart News Daily.

“China is obviously North Korea’s dominant trading partner. Over 90 percent [of] North Korea’s external trade is with China. We continue to press China to enforce all the sanctions against North Korea. China’s always said going back over 20 years now they don’t want to see North Korea with nuclear weapons, and I think they have good reason not to want to see North Korea with nuclear weapons because China ultimately doesn’t want to see Japan get nuclear weapons,” he said.

The pressure on China comes amid trade talks between Washington and Beijing. Bolton said the talks could be reaching their conclusion in the near future.

“We’re in the middle of a big trade negotiation now. The president is determined to do something about the imbalance of trade, the unfairness of China stealing our intellectual property over the years,” he said.

But Bolton said the issues also extended past trade.

“We’re worried about China’s effort to affect democracy in this country, to engage in surveillance, cyber warfare. Vice President Pence made a very important speech a couple of months ago at [the Hudson Institute] on the threat that China poses in that regard. So this is a very big issue, how do we deal with China in this century, probably the biggest international issue we face,” he said.

Bolton also refuted critics who have called the Hanoi Summit between President Trump and North Korean leader Kim Jong-un a failure.

“I think this is the press showing its bias; it cannot be a failed summit if the United States defends American interests,” he said. “What the president did was hold the door open for North Korea to say, ‘You can have this future, but you’ve got to give up your weapons of mass destruction.’ So far, the North Koreans haven’t walked through it.”

“But it’s hardly a failure, unless you believe — and there are some people who believe this … many of them were in the Obama administration — that a bad deal with a nuclear proliferator, like Iran in the case of the Obama administration, a bad deal is better than no deal. That’s not Donald Trump’s view, and obviously I agree with the president,” he added.

Bolton said what happened was that Kim brought a deal that was “not satisfactory.”

Kim reportedly offered to dismantle the Yongbyon reactor complex for some sanctions relief. Bolton said Trump instead gave him “several alternatives” that included the “big deal — North Korea gives up all of its weapons of mass destruction and ballistic missiles and in exchange there’s a very bright economic future for North Korea.”

Bolton said Trump also gave Kim a definition of denuclearization, so that both sides would be clear on what that meant and what would need to happen in order for the U.S. to accept a deal. “We gave them a definition, the president actually handed over a piece of paper — two pieces really, one in English, one in Korean, to Kim Jong-un that describes our definition of denuclearization,” he said.

Taeyong Cho, a top former South Korea diplomat, praised the president’s offer of a bigger deal in a recent article on 38 North, a prominent website that tracks North Korea. He wrote that Kim was “unprepared to consider this approach and ended up revealing that his idea of denuclearization was different from that of the international community.”

“By refusing to accept Trump’s offer to ‘go bigger,’ Kim Jong-un revealed that he has no intention of parting with his nuclear arsenal. Surely, North Korea will again try to dupe the U.S. and the international community. But it will not be easy this time,” he wrote.

He also applauded Trump giving Kim a definition of denuclearization. “No longer will North Korea be able to play the ambiguity game with impunity,” he wrote.