Homeland Security Secretary Markwayne Mullin said a man with direct ties to Iran's Islamic Revolutionary Guard Corps tried to enter the United States with the Iranian national soccer team during the World Cup.

"When we started doing the research on him, he had only been put in place since 2022, and we didn't allow him to board the plane," Mullin said in a TV interview Sunday. "The guy trying to get on the plane yesterday had direct ties to IRGC."

The Football Federation Islamic Republic of Iran called Mullin's allegation "an outright lie."

"The claim that an official representative of the Iranian football federation attempted to board a flight to enter the United States yesterday and was prevented from doing so is an outright and undeniable lie. This claim is so unfounded that those who made it are well aware that such an incident never occurred in the first place," FFIRI said.

"It is regrettable that a senior US official has resorted to spreading false statements and misinformation in order to justify restrictions imposed on members of the Iranian national team delegation," FFIRI added. 

"When a specific, verifiable, and individually targeted allegation is made and that allegation is fundamentally false, it naturally calls into question the credibility of the other accusations as well," FFIRI continued.

Iran's national team has been training in Mexico and is permitted to enter the U.S. one day before its scheduled World Cup matches.

The team entered the U.S. on Saturday before its match against Belgium on Sunday. Iran said it requested permission to enter the country two days in advance, but the request was denied, the Washington Examiner reported.

Iran has filed a complaint with FIFA, arguing the restrictions prevent players from properly adapting to local conditions, the Examiner reported.

Mullin said he has had multiple conversations with FIFA President Gianni Infantino about the travel restrictions.