Iran's football coach Carlos Queiroz has called on Nike to apologise to his team after the American sportswear firm said it could not supply the players with boots for the World Cup due to sanctions.
The Iranian squad have been left scrambling to sort out footwear ahead of their opening match against Morocco on Friday.
This follows the recent decision of the Trump administration to pull out of the international nuclear deal made three years ago, and to intensify restrictions on Iran.
"US sanctions mean that, as a US company, Nike cannot provide shoes to players in the Iranian national team at this time," Nike said in a statement as quoted by ESPN. "Sanctions applicable to Nike have been in place for many years and are enforceable by law."
That last statement has caused confusion and frustration in the Iranian football federation. Nike has previously supplied the Iranian team with boots, and did so at the 2014 World Cup when similar sanctions were in place.
However, the company says it cannot do so for the tournament in Russia because of sanctions against Iran.
"This last comment of Nike was, in my personal view, an unnecessary statement. Everybody is aware about the sanctions," Queiroz told Sky Sports. "They should come out and apologise because this arrogant conduct against 23 boys is absolutely ridiculous and unnecessary."
Some of Iran's players are understood to have asked non-Iranian players from their club teams to loan them boots, while others are said to have acquired them from friends or gone out to buy their own footwear in the shops.
Queiroz has also managed Real Madrid, worked under Sir Alex Ferguson at Manchester United, as well as coaching the national side from his native Portugal.