American singer Jennifer Lopez was supposed to perform official song at opening ceremony of World Cup in Brazil. However, her agent told FIFA ( organisers of tournament) that she has pulled out. The agent said: "Regretfully, Jennifer Lopez will not be attending this year's World Cup opening ceremonies." Neither star nor her agent gave specific reason why, but said it was due to "production issues". Lopez was going to join rapper Pitbull and Brazilian star Claudia Leitte onstage ahead of opening game between hosts Brazil and Croatia. FIFA announced on its website that song, "We Are One (Ole Ola)," would now be sung just by Pitbull and Ms Leitte. World Cup song has been tradition since 1966 World Cup in England. In recent World Cups, people have been unhappy that song has not represented the country hosting the competition. At the South Africa World Cup in 2010, Colombian singer Shakira sang the official song. In 1998, Puerto Rican star Ricky Martin sang the song for France World Cup. Many Brazilians do not like 2014 song. They say it has weak Brazilian rhythm, is mainly performed by non-Brazilian musicians and is sung largely in Spanish and English, with few seconds of Portuguese at the end. Brazilian composer and music critic Leonardo Martinelli said song has been "stripped of local colour".