BEIJING, April 21 (UPI) -- A senior U.S. official said the United States and China stand in "firm opposition" to North Korea's military provocations.
Ambassador Sung Kim, the U.S. special representative for North Korea policy, made the statement after meeting with Wu Dawei, China's special representative for Korean Peninsula Affairs in Beijing, Yonhap reported.
Kim called North Korea's actions "irresponsible," adding that Washington and Beijing are equally concerned about the possibility of a fifth nuclear test.
A number of South Korean government officials, including President Park Geun-hye, had said the test could "happen at anytime," and more than a few have pointed out that activities have picked up at the North's Punggye-ri nuclear site.
"I think that concern is shared by China and other parties of the six-party process that North Korea may conduct another provocative action," Kim said in Beijing.
"We call, we urge North Korea to refrain from any such provocation."
Bilateral ties between China and North Korea have been strained by Pyongyang's January nuclear test and February rocket launch.
Relations have also deteriorated after China agreed to implement United Nations Security Council sanctions after adopting Resolution 2270 in March.
The sanctions could have a serious impact on North Korea trade with China, Voice of America reported Thursday.
Pyongyang's economy is heavily dependent on China, and China is often the only market for North Korean natural resources, including anthracite coal, a key export.
According to North Korea Resource Institute in South Korea, the dependency is costing Pyongyang.
In the last five years, North Korea has lost $5.1 billion in potential revenue from mineral sales, owing to China's stronger bargaining power, NKRI stated.