The R&B singer claimed that Scherzinger's solo album Her Name Is Nicole has been pushed back several times in order for her to continue in the girl group, Ace Showbiz reports.
Hilson told the Daily Star: "I wrote 'Alienated', one of the songs on my album, for Nicole's solo project. It was a good album but she decided to go back to the Dolls instead of releasing it, well she was kinda forced to I think."
Scherzinger will reportedly leave the Pussycat Dolls to focus on her solo career after promotion for their Doll Domination LP is finished.
Speculation was fuelled further after the band's single 'Jai Ho!' was released under the name 'Pussycat Dolls featuring Nicole Scherzinger'.
In April, fellow group member Melody Thornton launched into a tirade about Scherzinger live on stage at a concert in Phoenix.