Aguilera, 34, has worked with Williams for her new album, reported Aceshowbiz.
"During my pregnancy, I had a meeting with him and just connected on where I want to take the next album," said Aguilera, who took a break from 'The Voice' when she was pregnant with her second child last year.
"And we started talking music, and he has one song in particular that I love," she said.