The official Web site of the rebel movement showed a picture of leader Velupillai Prabhakaran "addressing a group of Tamil intellectuals and disaster management planners" Monday in the northern town of Kilinochchi, the BBC reported Tuesday.
The state-run Sri Lanka Broadcasting Corp. reported last week that Prabhakaran had been killed by the tsunami.
He also has been criticized by the Sri Lankan press for not taking a higher profile in tsunami relief efforts in Tiger-controlled areas.
Prabhakaran was quoted on the Web site as saying, "Let this disaster not turn our people into a community dependent on relief aid, and I request you in earnest to formulate plans that would provide them with the impetus to build a future of their own."
The rebel leader said he was "shocked" by the scale of the devastation and called for greater efforts to protect children who were "psychologically scarred" by the disaster.
The Web site did not mention why he had not appeared until now. On Dec. 29 he made an announcement to the community but made no public appearance.