U.S. Secretary of State Rex Tillerson embarks Thursday on his second trip to China, seeking Beijing's cooperation on a "maximum pressure" campaign against North Korea's nuclear aggression amid heightened tensions on the Korean Peninsula.
In a meeting with Chinese Vice Premier Liu Yandong on Thursday, the top U.S. diplomat is seeking China's cooperation to curb North Korea's nuclear provocations and to pave the way for President Donald Trump's first visit to China in November.
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"We'll continue our discussions on a number of other issues that are important, and certainly North Korea will be on the table for discussion," Tillerson said before the first round of U.S.-China Social and Cultural Dialogue that's aimed at promoting people-to-people ties.
The U.S. is conferring closely with Chinese officials on Beijing's commitment to curb imports of North Korean coal, iron, iron ore, lead and lead ore, and seafood.
If fully implemented, the ban on those items could substantially reduce North Korea's revenues this year. North Korea earned $1.5 billion from the export of these items to China in 2016, according to the State Department.
No. 1 trading partner
China is North Korea's No. 1 trading partner. Washington says bringing China on board is key to cutting off Pyongyang's ability to earn hard currency.
"We've been rolling out sanctions on various entities in China," acting Assistant Secretary of State for Asian and Pacific Affairs Susan Thornton told U.S. lawmakers Thursday.
"All of these designations target North Korean trade, North Korean entities, North Korean illicit proliferation," Thornton said, adding that those measures will reduce Pyongyang's ability to earn hard currency and increase pressure on the regime.
Trade and investment also are high on the agenda for Tillerson's visit to Beijing. It follows one by U.S. Commerce Secretary Wilbur Ross, who has said China needs to provide fair and reciprocal treatment for American companies.
"We're working with China to rebalance our trade and our lopsided relationship in that realm, and ensure that China provides fair treatment to U.S. companies in ways that create U.S. jobs," State Department spokesperson Heather Nauert said Thursday.
Energy embargo unlikely
Experts say China is very unlikely to completely cut off energy supplies to North Korea, but Beijing appears ready to cut down oil supplies.
Atlantic Council senior fellow Robert Manning said China can do a number of things, including closing a border bridge or permitting 24/7 U.N. monitoring of traffic to and from the road.
"The U.S. has intelligence that Pyongyang is either importing or exporting nuclear and/or missile components or other sensitive items; Beijing can and should cooperate in intercepting them," Manning told VOA.
But Carnegie Endowment for International Peace's Asia Program director Douglas Paal said China's influence over North Korea is limited.
"The North is very reluctant to take instructions from China. It will exploit whatever it can get from China, but it doesn't look for political guidance from China. So this is a problem we [the U.S.] and South Korea are going to have to handle directly with North Korea as we go forward," Paal told VOA.
Trump's tweets
North Korean intermediaries reportedly approached Paal to help to decipher President Trump's tweets.
"In January, the North Koreans had to see Trump's tweet, which was criticizing South Korea and talking about possible talks, meetings, and discussing issues with the North Korea leader. So they probably were looking for some clues of what this all means. Since then, of course, most of the tweets had turned very negative on North Korea," Paal said.
"They probably could use some help to understand what the real policy of the Trump administration is. So it's reasonable for them to be out asking," Paal added.