The director of new documentary Kurt Cobain: Montage Of Heck has revealed there are plans to release an album of the late Nirvana star's lost recordings this summer.

Brett Morgen discovered over hundreds of hours of material Cobain recorded while researching his film, which will debut on U.S. TV next week (beg04May15) - after wowing critics at the Sundance Film Festival in Utah in January (15).

Morgen tells U.S. publication Bedford + Bowery, "We’re going to be putting out an amazing album this summer... It will feel like you’re kind of hanging out with Kurt Cobain on a hot summer day in Olympia, Washington as he fiddles about. It’s going to really surprise people."

He adds, "It’s not a Nirvana album, it’s just Kurt and you’re going to hear him do things you never expected to come out of him."