FIFA president Gianni Infantino has indicated Donald Trump's controversial travel ban could prevent the United States from hosting the World Cup.
The United States is favourite to win the right to host the 2026 World Cup, either on its own or in a cross-border bid with either, or both, Mexico and Canada.
But President Trump on Monday signed a new executive order banning immigration from six Muslim-majority countries, which could have implications for the nation's ability to host football's biggest tournament - and the 2024 Olympic and Paralympic Games which Los Angeles is bidding to stage.
Infantino said in London on Thursday: "When it comes to FIFA competitions, any team, including the supporters and officials of that team, who qualify for a World Cup need to have access to the country, otherwise there is no World Cup. That is obvious."
The competition will be expanded from 32 to 48 teams in 2026.
Of the countries affected by the executive order, Iran has the highest-ranked team in the FIFA rankings at 33rd and they have qualified for four World Cups. Syria, Libya, Somalia, Sudan and Yemen are the other countries on the list.
FIFA is finalising the requirements for bidding for the 2026 tournament, which in 2018 will be hosted in Russia and in 2022 in Qatar.
Infantino added: "Mr Trump is the president of the United States of America and as such of course (I have) huge respect for what he does.
"He's in charge, together with his government, to take decisions that are best for his country. That's why he has been elected.
"In the world there are many countries who have bans, travel bans, visa requirements and so on and so forth.
"We are now in the process of defining the bid requirements.
"The requirements will be clear. And then each country can make up their decision, whether they want to bid or not based on the requirements.
"It's general sporting criteria."