Iran are due to play New Zealand and Belgium in Inglewood, California, and Egypt in Seattle in Group G. They could feasibly face the United States in the next round if both teams finish second in their groups.
Iranian officials have said they do not want to boycott the tournament but that it is not possible for the national team to travel to the US amid ongoing US and Israeli attacks on the country.
But FIFA President Gianni Infantino said in a statement on Thursday that "we have a schedule" and "we want the World Cup to go ahead as scheduled."
It would be unprecedented in modern World Cup history for a team's schedule to be changed after the draw for political reasons.
"FIFA can't solve geopolitical conflicts," said Infantino, who recently invented a so-called "FIFA peace prize" to be awarded to US President Donald Trump three months before he launched a war against Iran.
"We are committed to using the power of football and the World Cup to build bridges and promote peace as our thoughts are with those who are suffering as a consequence of the ongoing wars," he said.
Also on Thursday, FIFA fined the Israel Football Association (IFA) 150,000 Swiss francs ($190,000 / €164,000) for breaching anti-discrimination regulations.
The Israeli federation was found guilty of "tolerance of politicized and militaristic messaging within football contexts" notably by far-right supporters of Israeli club Beitar Jerusalem, and the "systemic exclusion of Palestinians from football infrastructure in Israeli settlements."
In addition to the fine, the IFA has been ordered to display "a significant and highly visible banner with the words 'Football Unites the World – No to Discrimination' alongside the Israel Football Association's logo" at its next three home matches.
Israel has only ever qualified for the World Cup once (Mexico 1970) and will not be at the 2026 edition after finishing third in their qualifying group behind Norway and Italy.
Read: Iran Says It's Boycotting the U.S., Not FIFA World Cup
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