Barry Dennen published his memoir My Life with Barbra: A Love Story in 1997, detailing his romance with the entertainer over 50 years ago.
Dennen, 67, claims he coached Streisand after they shared the stage in 1959 off-Broadway play The Insect Comedy, and admits he refused Streisand's request to return three performance tapes he recorded during their relationship.
The recordings include a rehearsal at a New York nightclub of songs including Keepin' Out of Mischief Now, I Want To Be Bad, Lover Come Back to Me and Who's Afraid of the Big Bad Wolf.
He tells the New York Post, "I (refused to give the tapes back). I said 'No. They are the only thing I have left of our collaboration' I'm a little trepidatious. I don't know what the fallout will be. I don't like upsetting Barbra, and I don't want her fans angry at me.".
The tapes are set to be auctioned off on MomentsInTime.com, but Streisand is moving to block the sale.
A spokesman for Streisand says, "Our lawyers are dealing with this.".