Foreign Secretary Nirupama Rao will undertake a three-day visit to Sri Lanka from Monday. She is expected to visit the north eastern provinces of Sri Lanka -- including Vayunia, Yazhpanam and Trincomalee -- to check the rehabilitation of the Tamil population, who were displaced by the military's offensive against the Liberation Tigers of Tamil Eelam. Rao is also expected to prepare the ground work for the official visit of External Affairs Minister S M Krishna to Colombo.