The players have been practicing with the shoes, which they received before beginning their training ahead of the World Cup.
The Iranian football team was left last minute to figure out their footwear dilemma after the firm Nike said they could not supply the players with boots for the World Cup.
"The sanctions mean that, as a USA company, we can not provide shoes to players in the Iran national team at this time", Nike said in a statement Friday.
"Sanctions applicable to Nike have been in place for many years and are enforceable by law".
ESPN reported Monday that the decision follows the USA withdrawing last month from the Iran nuclear deal.
Members of Iran's soccer team have resorted to asking other players to loan them footwear or individually purchasing cleats, ESPN reported. Federation Internationale de Football Association did not respond to an ESPN request for comment on the letter or its potential response.More news: Turkey hails historic North Korea, US summit
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The head coach of Iran's national team, Carlos Queiroz, told reporters "players get used to their sports equipment, and it's not right to change them a week before such important matches".
United States sporting goods giant Nike confirmed Monday it had stopped supplying Iran's soccer team with soccer shoes ahead of the World Cup due to sanctions. "We know their team very well but I suspect they know very little about us".
Sports Illustrated reported most teams in the World Cup - an worldwide tournament played every four years - have a footwear sponsor.
That run includes 22 matches and even saw Iran as the first team to qualify for Russian Federation. A warm-up exhibition match with Greece was cancelled at the last minute due to political concerns and basic tasks, such as booking hotels and flights or doing anything that involves transferring money, require workarounds because of the sanctions against Iran.
Iran's first game is Friday against Morocco. Spain and Portugal round out the deadly Group B.