The paper reported that Tony Award winner Sondheim, 81, has written "20 or 30 minutes" of the new piece. "Having spent the better part of four years writing two books [of his collected lyrics], I'm really rusty," he told the paper. "I sit at the piano and think, 'Where's middle C?' Any muscles, as you know, atrophy when you don't use them, and I haven't been using my musical muscles."

Sondheim told Playbill.com on Feb. 29, "It's an idea I've had for a long time and it springs indirectly from a moment in a play of David's." He left it at that. Ives declined to comment.

The last "new" full work from the Pulitzer Prize- winning songwriter was Road Show (2008 at The Public Theater), a revision of a past show called Bounce, though he did pen a new song called "God" for Sondheim on Sondheim on Broadway in 2011.

Pulitzer Prize winner Sondheim wrote music and lyrics for the Broadway musicals Company, A Funny Thing Happened on the Way to the Forum, A Little Night Music, Follies, Sunday in the Park With George, Merrily We Roll Along, Sweeney Todd, Pacific Overtures, Passion, The Frogs, Assassins and Into the Woods.

Ives' plays includes The Heir Apparent (adapted from Regnard play), The School for Lies (adapted from The Misanthrope), the Helen Hayes Award-winning The Liar (adapted from Pierre Corneille's play), Is He Dead? (adapted from the Mark Twain play), Polish Joke and Irving Berlin's White Christmas.