American singer-song writer Gwen Stefani has revealed she was concerned that she had accidently copied the lyrics for her new Christmas song from a song she hea

During an interview on "The Tonight Show Starring Jimmy Fallon", to promote her new Christmas album, the pop star said the words for "Christmas Eve" came so effortlessly while she was jogging, she was worried that she had unknowingly stolen them.

She said: "I was running and I thought, 'Ooh maybe I'll try singing something, maybe something will come.

"And the whole chorus to this song Christmas Eve came, it was like a prayer.

"I was like, 'Oh my gosh, I have to run back!'

Then she added: "I'm like, 'Did I steal this?

"Is this from church because I feel like I know this song?'

"I was convinced that I stole it.

"I went back and I ended up finishing it."

However, Stefani said her parents assured her that the song was completely new and was not from a song she heard during a church service.