FIFA president Gianni Infantino has urged the 32 nations preparing for the most political World Cup in the modern era to focus on the game in Qatar and avoid handing out lessons in morality.

A letter imploring teams to "let football take center stage" was sent by Infantino and FIFA secretary general Fatma Samoura ahead of intense media focus on coaches and players when World Cup squads are announced next week.

"Please, let's now focus on the football!" Infantino and Samoura wrote, asking the 32 competing federations to "not allow football to be dragged into every ideological or political battle that exists."

Qatar was picked to host the World Cup in 2010 and it has since received scrutiny over its treatment of low-paid migrant workers and its laws criminalizing same-sex relationships. 

Around 1.2 million international visitors are expected in Qatar during the tournament.