Robert Plant and Alison Krauss will kick off a world tour in support of their acclaimed 2007 album "Raising Sand" with a handful of dates in the U.S. and Europe this spring.

The first leg begins in Louisville, Ky., on April 20 and continues to Knoxville, Tenn., on April 22, Chattanooga, Tenn., on April 23 and Birmingham, Ala., on April 26. The tour's 11-date run in Europe follows in May.

The duo will be joined on stage by producer and musician T Bone Burnett. Tickets for the April U.S. dates go on sale Jan. 25. A longer run of North American shows is planned for June and July, but dates and details have not yet been announced.

The Plant/Krauss trek, long in the works, would likely complicate the scheduling of a potential full Led Zeppelin tour, which has been widely speculated following the legendary band's one-off December reunion concert in London.

"Gone Gone Gone (Done Moved On)," the single from "Raising Sand," is currently up for a best pop collaboration with vocals Grammy. The album bowed at No. 2 on The Billboard 200 in October.