The visit to China, which was a signatory to a since-abandoned 2015 nuclear agreement that reined in Tehran's nuclear programme, was announced by foreign ministry spokesman Esmaeil Baqaei at a weekly press conference on Monday.

Araghchi previously visited China in December.

The Chinese foreign ministry did not confirm the visit when asked by AFP, but said "China and Iran maintain exchanges and interactions at different levels and in different fields".

The 2015 accord, formally known as the Joint Comprehensive Plan of Action (JCPOA), was also signed by four other permanent UN Security Council members -- Britain, France, Russia, and the United States -- along with Germany and the European Union.

Those countries were party to the agreement and so "consultations must continue with them," Baqaei said.

US President Donald Trump withdrew from the agreement in 2018, during his first term, which prompted Iran to breach its terms a year later.

Since returning to office, Trump has called for nuclear talks with Tehran while at the same time threatening military action.

Western nations have long accused Iran of pursuing nuclear weapons, something Tehran denies.

A third round of US-Iranian talks, mediated by Oman and involving Araghchi and Trump's Middle East envoy Steve Witkoff, are due to take place on Saturday, Iran has said.

China is Iran's largest commercial partner and the main buyer of its oil, with Tehran still under crushing US sanctions.

Around 92 percent of Iranian oil heads towards China, according to Iranian media, and is often sold at a considerable discount.

In 2021, Tehran and Beijing signed a comprehensive 25-year strategic agreement covering energy, security, infrastructure and communications among others areas.