Iran's football chief has said he wants a guarantee the Islamic Revolutionary Guard Corps (IRGC) will not be insulted by the US during the World Cup.
Mehdi Taj and other delegates did not make it to FIFA's annual congress in Canada last week.
He said they headed back of their own accord after disrespectful treatment by border officials.
However, Canada's immigration minister told parliament Mr Taj's visa had been cancelled mid-flight due to his ties to the IRGC.
Canada and the US are among those who classify the IRGC - a paramilitary force integral to upholding the Iranian regime - as a terror group.
Mr Taj told Iranian broadcaster IRIB he would be looking for assurances about their treatment by the US at the tournament.
"We need a guarantee there, for our trip, that they have no right to insult the symbols of our system - especially the Islamic Revolutionary Guard Corps," said the Iranian FA (FFIRI) chief.
"This is something they must pay serious attention to. If there is such a guarantee and the responsibility is clearly assumed, then an incident like what happened in Canada will not happen again."
He suggested Iran could leave the tournament if they did not receive assurances on the matter.
Mr Taj was a senior IRGC official before becoming president of Iran's football association.
He added: "We are going to the World Cup, for which we qualified, and our host is FIFA - not Mr Trump or America.
"If they accept hosting us, then they must also accept that they must not insult our military institutions in any way.
"Because if they do, then naturally it could create the same kind of situation that happened in Canada, where there was a possibility we might have to return.
"So there must be this kind of guarantee so that we can go with peace of mind."
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FIFA has apologised for the "inconvenience and disappointment" caused in the Canada incident and invited Iranian officials to a meeting at its Swiss headquarters on 20 May.
Marco Rubio, the US secretary of state, said the Iranian team is welcome but no IRGC-linked officials will be admitted.
Gianni Infantino, the head of FIFA, insisted last week that Iran would not be excluded despite speculation players could be barred from entering the US.
The team are scheduled to play twice in Los Angeles in the group stages and once in Seattle.
Iran had asked for all its matches to take place in Mexico but the request was denied.
The US, Canada and Mexico are co-hosting the June 11 to July 19 World Cup.
(c) Sky News 2026: Iran football chief wants 'no insults' guarantee for IRGC ahead of World Cup
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