Haggard -- whose country hits include "Okie from Muskogee," "If We Make It Through December" and "Ramblin' Fever" -- is set to release "Unforgettable" next week. The CD includes such classic tunes as "Stardust," "As Times Goes By," "Cry Me a River" and the title song.
Haggard told United Press International he decided to record an album of standards because they are "the greatest songs of all time," and because he was finally ready to do them.
"It's been a lifelong struggle getting to the place where I could this sort of thing," he said. "I'm not looking down -- I'm trying to step up a notch."
Haggard's most recent album, 2003's "Haggard Like Never Before," was notable for "That's the News" -- his commentary on media fixation with celebrity and how it undermines coverage of more serious matters, such as the war in Iraq.
Capitol Records Nashville said it would soon announce details on Haggard's upcoming collaboration with legendary producer Jimmy Bowen, Haggard's first album of new music for Capitol in 25 years.