(Bloomberg) -- China’s foreign minister voiced opposition to the U.S.’s unilateral sanctions against Iran and pledged to support Tehran’s efforts to safeguard its interests, as the U.S. ratchets up pressure on the Islamic Republic’s economy.

Wang Yi told Iranian Foreign Minister Mohammad Javad Zarif during a meeting in Beijing on Friday that China is willing to work alongside Iran to “rule out the disruptions of certain complications” to make possible the complete implementation of the 2015 nuclear accord, according to a statement published online by the Chinese Foreign Ministry.

China is the last stop on Zarif’s Asian tour, after visits to Japan and India this week. He aims to drum up political and economic support for Iran, amid rising tensions in the Middle East and U.S. pressure to scrap the landmark nuclear deal that restricted Iran’s nuclear program in return for sanctions relief.

On Thursday, Zarif met with Japanese Prime Minister Shinzo Abe, who urged Iran to abide by the accord, of which Zarif was a key negotiator.

Read more: Japan Calls on Iran to Abide by Nuclear Deal and Reduce Tensions

Rising Tensions

On May 2, the Trump administration -- which has ditched the nuclear deal -- revoked waivers on Japan and several other buyers of Iranian crude, spiking tensions in the Gulf. It left Iran with a stark choice: go along with the U.S. and stop all uranium enrichment, or abandon some of its obligations under the 2015 accord, facing a rupture with European signatories.

Read more: Iran’s Risky Nuclear Gambit Fueled by Trump’s Enrichment Curbs

But China, one of the world’s biggest buyers of Iranian oil, hasn’t committed to halt imports from Iran. It has advocated for the deal to remain in tact, with Chinese Foreign Ministry spokesperson Geng Shuang saying May 7 that the government “applauds Iran’s faithful implementation.”

“China is in a dilemma over the Iran issue,” said Shi Yinhong, a professor of international relations at Renmin University in Beijing. “As its relations with the U.S. deteriorate, China has little room for mediation. China doesn’t have any concrete measures it can take to safeguard its oil security.”

Chinese crude imports climbed to a record high last month, as a drive to stock up on Iranian oil before the sanctions exemptions expired offset the effect of maintenance shutdowns by local refiners.

‘Very Nervous’

“China is very nervous for sure as Iran’s largest oil importer,” said Zhu Feng, dean of the Institute of International Relations at Nanjing University. But it “has limited options to respond.”

Still, it may not face a choice following the U.S. move to end the sanctions waivers. “The explosive development will directly affect China’s overseas energy procurement and transportation,” Zhu said.

--With assistance from Linly Lin.

To contact Bloomberg News staff for this story: Dandan Li in Beijing at dli395@bloomberg.net

To contact the editors responsible for this story: Brendan Scott at bscott66@bloomberg.net, Karen Leigh, Kathleen Hunter

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