Jennifer Lopez has pulled out of the World Cup opening ceremony in Brazil, four days before the tournament kicks off.

E! News reported that Lopez was scheduled to perform the official World Cup song, "We Are One," with rapper Pitbull and Brazilian singer Claudia Leitte at the Thursday opener in Sao Paulo. A representative for the singer said Lopez cancelled her performance due to unspecified "production issues."

"For production issues, Jennifer Lopez, one of the artists of the official song 'We Are One,' will not be able to perform at the FIFA World Cup opening ceremony," it said in a statement.

According to the Associated Press, the song has not become a hit in Brazil. Many Brazilians were reportedly disappointed in the scarcity of Portuguese lyrics. Cuban-American rapper Pitbull and Brazilian singer Claudia Leitte will sing the official tune "We Are One" - accompanied by Brazilian drumming collective Olodum.

"To be performing 'We Are One' to the world, especially in such a beautiful country like Brazil, is going to be a lot of fun. But more than this, it is going to show the world that music is the universal language," he said in a statement released by FIFA.

Brazil will be playing against Croatia in Sao Paulo during the opening game on Thursday. More than 60,000 people will be in Sao Paulo's Corinthians Arena to watch the ceremony and kick-off. Around a billion people are expected to tune in on TV worldwide.