"Seyyed Abbas Araghchi arrived in Beijing... at the head of a diplomatic delegation. During this visit, our country's Foreign Minister will discuss bilateral relations and regional and international developments with his Chinese counterpart," Fars reported.

China is a key customer for Iranian oil, defying sanctions imposed by the United States as Washington seeks to choke off revenue to Tehran.

Araghchi's trip comes before US President Donald Trump's scheduled visit to China on May 14-15 to see President Xi Jinping -- a trip he delayed after the United States and Israel attacked Iran.

US Secretary of State Marco Rubio on Tuesday called on China to put pressure on Araghchi to loosen Tehran's chokehold on the Strait of Hormuz, through which one-fifth of the world's oil once transited.

"I hope the Chinese tell (Araghchi) what he needs to be told, and that is that what you were doing in the straits is causing you to be globally isolated," Rubio told reporters.