Omar Artan was not allowed to enter the United States. (Getty Images/FIFA: Hector Vivas)
In short:
Omar Artan was denied a chance to make his World Cup debut after being barred from entering the United States.
Artan says he is in good spirits as he returns home to Somalia.
What's next?
The World Cup is set to begin on Friday at 5am AEST.
Somali football referee Omar Artan is returning home after being denied a chance to make his World Cup debut when the United State barred him from entering.
Artan was expected to become the first Somali to officiate in a World Cup match.
Speaking at Istanbul Airport before boarding a flight to Somalia, Artan said he was in good spirits.
"I feel very good now," Artan said.
"I wanted to thank FIFA for supporting me all the way and the Somali people, also. So, I am very grateful for FIFA and CAF, also."
Somalia's government said it had unsuccessfully tried to negotiate with the US and FIFA so Artan could enter the country.
"His international achievements are a source of honour and pride for the Somali people," Somalia's sports ministry said in a statement.
The Somali Football Federation said it had not received an official explanation for why Artan was denied entry.
It was working with FIFA and the relevant authorities to understand the circumstances.
A FIFA spokesperson said the organisation was "not involved in host country immigration processes, including visa adjudications, and has been informed by authorities that Mr Artan's status will not be changed at present".
Artan would also be unable to referee games in Mexico and Canada.
FIFA's head of match officials, Pierluigi Collina, has set up a training hub in Miami for the 140 referees and assistant referees participating in the event.
These officials are required to stay at the training base for logistical and security reasons; therefore, it would not be possible for Artan to referee games in Canada and Mexico without setting foot in the US.
US Customs and Border Protection said that, without naming him, a Somali national who arrived at Miami International Airport from Istanbul on Saturday was deemed inadmissible due to vetting concerns.
Last year, the Trump administration imposed a travel ban on citizens of 12 countries, including Somalia.
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