Iran and China on Saturday signed a series of agreements worth $4 billion (2.8 billion euros) for infrastructure projects as part of a broader bid to boost trade volume between the two nations, Iranian state media reported.

As part of a $500 million (354 million euros) deal, China agreed to provide Iran with 60 energy recovery incinerators, which are to be installed within a year in major cities and in Iran's northern tourism hub along the Caspian sea.

The bilateral agreements span cooperation in water, mining, energy and industrial sectors.

China also pledged to boosts its imports of Iranian mineral products, state TV reported.

"China is now the leading economic partner of Iran and there are plans for increasing last year's trade volume of $30 billion (21 billion euros) to $100 billion (71 billion euros) in the future," Iranian Vice President Mohammad Javad Mohammadi-Zadeh told state television.

The agreements were signed during a visit by He Guoqiang, a senior executive of the Chinese Communist Party, who heads a delegation visiting Iran.

He was received by Iranian President Mahmoud Ahmadinejad.

"Bilateral trade will reach $40 billion (28 billion euros) this year," the Chinese ambassador to Tehran told IRNA recently.

China and Iran have become major economic partners in recent years, partly thanks to the withdrawal of Western companies in line with sanctions against the Islamic republic over its contentious nuclear drive.

Beijing, which now buys about 20 per cent of Iranian crude, opposes the policy of the United States and its European allies seeking to strengthen UN sanctions against Iran.