Lady GaGa has finally spoken out about her decision to block the release of her collaboration with Cher, insisting the song wasn't "up to par" because they recorded their vocals separately.

The Believe hitmaker has been candid about her frustration with Gaga after she refused to let the song, titled The Greatest Thing, feature on Cher's new album, but an unfinished version of the track was leaked online last month (Aug13).

Gaga has now opened up about the dispute over the song, admitting she didn't like the finished product because it wasn't a true collaboration between the two artists.

Speaking on U.S. Tv show Watch What Happens Live, Gaga says, "I have so much respect for Cher and I love Cher so much that when we do a duet that we release, I wanted it to be something that was really really special and... we just didn't have time to work on it together... We recorded it (separately)... and I wrote the song a long time ago.

"To be fair, if I was writing a song for Cher now, I would want to hear her album and I want to know where she is in her life. I would want to talk to her about where's she is going musically, and I didn't get to do any of those things. So I didn't want to put out something that wasn't up to par with what Cher has put out before. It's not really about me, it's more about her. Because it's Cher!"