Speaking at a book signing of her novel Priceless, Nicole stated "I'm not down [with that]," when quizzed about Joel’s comments that he'd "love Lionel to play a song".
The 29-year-old star is engaged to musician boyfriend Joel Madden, and recently confirmed their wedding will take place soon. But Nicole is determined there will be no guest singing appearance from Lionel at the event.
Nicole was in a playful mood at the event, jokingly refusing to confirm that she would be getting married at all. It was left to Joel to fill in the details.
The couple have been together since 2006 and have two children, daughter Harlow, two, and 13-month-old son Sparrow.
"Are we getting married? Of course we are, we're engaged," he said during an interview about Good Charlotte's new album Cardiology. "I don't know when it could happen with our schedules. I'm working this next year and a half."
Although fiancé Joel favoured the idea of Lionel crooning a tune, Nicole was quick to dismiss the notion.