LOS ANGELES: Ne-Yo has cast doubt on Lindsay Lohan's pop return after the actress/singer abandoned plans to record more songs with the R&B hitmaker.

The Miss Independent singer worked with Lohan in 2008 on her single Bossy and made arrangements to head back into the studio to record more music together for her forthcoming third album.

But Ne-Yo has not heard from Lohan since and he's not sure he ever will.

He tells PopTart, "We were doing some stuff and then it just fell off and hasn't got back on. I'm not gonna hold my breath."

However, the smooth star is refusing to give up on the project altogether and has called on Lohan to get in touch when she's "ready".

He adds, "Lindsay, when you're ready to get it in (finish their collaborations), give me a call."

Lohan announced plans for her next album, tentatively titled Spirit in the Dark, in 2007 after signing with Universal Motown but the project has no expected release date.