The US president on Tuesday ordered that payments amounting to $400 million be halted pending a review of the WHO’s role in allegedly “severely mismanaging and covering up the spread of the coronavirus”.
The death toll from the COVID-19 pandemic has topped 125,000 around the world, with more than two million people infected by the disease since December.
Zarif likened the funding freeze to Washington’s “maximum pressure” campaign against the Islamic Republic.
“The shameful defunding of WHO amid a pandemic will live in infamy,” Zarif wrote on his Twitter account.
“The world is learning what Iran has known & experienced all along,” he said.
“US regime’s bullying, threatening & vainglorious blathering isn’t just an addiction: it kills people.”
Iran itself is battling the Middle East’s deadliest outbreak which has left over 4,700 dead and more than 76,300 infected.
It has repeatedly called on the Trump administration to reverse its sanctions policy, which has been opposed even by some US allies, particularly since the pandemic hit.