A trade war between the US and China might be an unlikely boon to Iran’s pistachio exports which have resurged following the lifting of sanctions on Tehran.

China has announced retaliatory tariffs of between 15 and 25 percent on some imports from the US, including nuts, in response to steep duties on some Chinese goods announced by the Trump administration.

US pistachio growers, many of whom voted for President Donald Trump, say the spat is a serious competitive blow.

The new tariff “impacts our ability to compete with our competitors from Iran,” Richard Matoian, executive director of the American Pistachio Growers, said on Wednesday.

China has existing duties of 5 percent on raw pistachios and 10 percent on roasted pistachios from the United States, but the additional 15 percent tariff is far above what American farmers can stomach.

US and Chinese flags in Washington. China has announced plans for reciprocal tariffs on $3 billion of imports from the US. (Photo by AP)

"When we compete with other countries for market share, such as Iran, we could have our prices higher than theirs, causing Chinese buyers to shift to Iranian pistachios," Matoian said.

China is the biggest customer, accounting for 50% of Iran’s pistachio nut sales. Other major clients are Japan, Hong Kong, the European Union, and Arab countries.

"When the US had a low production year in 2015 and prices rose, Chinese buyers shifted their buying to Iran, but as we had record production of pistachios in 2016, Chinese buyers shifted to the U.S. as the prices moderated," Matoian said.

California is on course to suffer most from the dispute because pistachios are the US state’s biggest agricultural exports to China which bought $531 million worth of the nuts in 2016.

The most populous US state is home to 99% of US pistachio orchards. Over the years, California has traded the title of world’s top pistachio producer with Iran.

The decade-old pistachio industry in the United States has grown rapidly to a $1.5-billion business, with the Kerman variety – getting its name from a desert city in southeast Iran - being the dominant cultivar.

Over the past decade, the US has doubled the acreage devoted to pistachio plantation and turned to a major rival for Iran.

Pistachio nuts were the top foreign exchange earner among Iran's agricultural exports at $972 million in the nine months since March 2017, its ministry of agriculture said last month.

According to head of the Iran-China Chamber of Commerce Asadollah Asgaroladi, 250,000 tonnes of pistachio nuts are produced a year, of which 150,000-160,000 tonnes are exported.

The delicacy also has its customers in the United States where it is allowed along with Iranian caviar, saffron and carpets for limited business with the US under a nuclear deal which went into effect in January 2016.