Iranian President Hassan Rouhani on Saturday hailed a "new chapter" in relations with China and the two countries vowed to boost their economic ties.

China and Iran aim to build economic ties worth up to $600 billion within the next 10 years, Rouhani announced, after talks with President Xi Jinping, who was paying a State visit in Iran.

The two leaders oversaw the signing of 17 agreements in areas including politics, the economy, security and cooperation on peaceful nuclear energy.

With the Chinese president's visit to Tehran and our agreements, a new chapter has begun in Iran-China relations, Rouhani said in a speech.

It was the first visit to Iran by a Chinese president in 14 years and came just days after sanctions against Tehran were lifted under a historic nuclear deal with world powers.

"Iran is China's major partner in the Middle East and the two countries have chosen to boost bilateral relations," state news agency IRNA quoted Xi as saying. "China and Iran are two important developing countries that must continue regional and international cooperation," Xi added.

Analysts said the region is crucial to Xi's signature foreign policy initiative known as the "Belt and Road" initiative. China, the world's second-largest economy, also relies heavily on energy from the Middle East.

Trade between the two countries was worth $52 billion in 2014. According to Iranian media, more than one third of Iran's foreign trade is with China.

The two countries agreed to enhance cooperation including in fossil and renewable energy, transportation, railways, ports, industry, commerce and services, said the statement published by Mehr news agency.

In the statement Iran welcomed China's commercial "belt" and the "21st Century Maritime Silk Road" projects, pledging to help the initiative. China has committed to "invest and finance upstream and downstream energy projects in Iran," it said.

Xi on Saturday met supreme leader Ayatollah Ali Khamenei, who said Tehran "would never forget" China's cooperation during the years of international sanctions against Iran.

"The Islamic Republic of Iran has always sought relations with reliable and independent states like China," Khamenei's website quoted him as saying.

Xi was quoted as saying that "the economies of Iran and China complete one another". Countries on the Silk Road route can "protect their interests against the American pattern of disrupting the regional economic balance by boosting cooperation," Xi added.

Xi's tour, which concluded on Sunday, his first of the Middle East as China's president, has also took him to Saudi Arabia and Egypt.

In Cairo, Xi offered $55 billion in loans and investments to the Middle East, a region where China wants to strengthen its economic presence.