FIFA have written to World Cup teams urging them to focus on the soccer in Qatar and not let the sport be dragged into ideological or political "battles".
The letter from FIFA president Gianni Infantino and the governing body's secretary general Fatma Samoura follows a number of protests made by World Cup teams, on issues ranging from LGBTIQ rights to concerns over the treatment of migrant workers.
"Please, let's now focus on the football!" Sky News quoted Infantino and Samoura as saying in the letter to the 32 nations contesting the World Cup.
"We know football does not live in a vacuum and we are equally aware that there are many challenges and difficulties of a political nature all around the world.
"But please do not allow football to be dragged into every ideological or political battle that exists."
FIFA was unable to provide immediate comment when contacted by Reuters.
The World Cup, the first held in the Middle East, starts on Nov. 20.
Australia's soccer team last week spoke out against Qatar's record on human rights and same-sex relationships.
Denmark's players will travel to the World Cup without their families as a protest against the country's human rights record, the Danish FA (DBU) told local media last month.
Football Australia confirmed the receipt of the letter from FIFA on Friday, but declined further comment. Reuters also contacted the DBU for comment.
World Cup organisers have said that everyone, no matter their sexual orientation or background, is welcome, while also warning against public displays of affection.
Qatar has acknowledged there are "gaps" in its labour system but the World Cup has allowed the country to make progress on worker rights.
"At FIFA, we try to respect all opinions and beliefs, without handing out moral lessons to the rest of the world," Infantino said in the letter, according to Sky.
"One of the great strengths of the world is indeed its very diversity, and if inclusion means anything, it means having respect for that diversity. No one people or culture or nation is 'better' than any other.
"This principle is the very foundation stone of mutual respect and non-discrimination. And this is also one of the core values of football. So, please let's all remember that and let football take centre stage."
