The Oscar-winning songwriters behind Let It Go, the hit song from the blockbusting Disney cartoon Frozen, have revealed that the word "God" is banned from Disney movies.

Speaking to Terry Gross on the National Public Radio (NPR) show Fresh Air, Robert Lopez and Kristen Anderson-Lopez explained that Disney was not a "sanitized" corporate environment but that "one of the only places you have to draw the line at Disney is with religious things, the word God". Lopez went on to say: "You can say it in Disney but you can't put it in the movie."

The revelation is likely to draw the ire of conservative Christian commentators who have already targeted Frozen for its supposed pro-gay propaganda. In March, Pastor Kevin Swanson of the Reformation Church, denounced the film as "very evil", and that Disney was "one of the most pro-homosexual organisations in the country".

Lopez and Anderson-Lopez, who are married, also explained that they first had the idea for the song while walking through Prospect Park in Brooklyn, and were so enthusiastic about it that they stood on the park picnic tables to improvise. According to Lopez it took just a day and a half to finish writing.

Let It Go has proved controversial thematically due to its message of empowerment, and Anderson-Lopez confirmed the "anti-princess" thrust of her work. She cited a song called We Know Better, which was cut from the final film but remained on the soundtrack CD, as "my very strong strike across the bow at all princess myths … it basically was these two princesses bonding over all of the things that the world expects and thinks of them."