Iran's president says the country seeks greater cooperation with Beijing and Moscow to confront what he called Washington's unilateralism, just a few weeks before Donald Trump restores his so-called maximum pressure policy aimed at isolating Iran.

"The United States pursues authoritarianism and unilateralism on the international stage," Pezeshkian said in a meeting on Wednesday with China's vice premier Zhang Guoqing in Tehran.

"We are determined to expand our cooperation with China and Russia to counter unilateralism," the Iranian president said.

The government is working to implement the 25-year agreement between Beijing and Tehran, he said.

Announced in 2016, the comprehensive strategic partnership aimed to increase bilateral trade to $600 billion by 2026. However, trade volume reached just $12.5 billion last year according to the International Monetary Fund.

China remains Iran's largest trade partner and purchases nearly all of Iran's crude oil in defiance of US sanctions. Nonetheless, Chinese companies have secured substantial contracts with other regional players, including Saudi Arabia and the UAE, totaling billions of dollars.