US president Donald Trump's threat to impose sanctions on countries that trade with Iran may derail New Zealand's work to rebuild what was once a huge market for farmers. Exports to Iran totalled $120 million last year, with dairy products making up three-quarters of that. When trade peaked in the 1980s, Iran was buying a quarter of New Zealand's sheepmeat exports. New Zealand's special agricultural trade envoy Mike Petersen visited Iran in 2017 with a delegation looking to rebuild the redmeat trade after two decades of sanctions came to an end. He told RNZ political reporter Benedict Collins the picture was brighter then than it is now.