The leader of Sri Lanka's Tamil Tiger rebels has served an ultimatum to the island's new government that unless the grievances of the ethnic Tamil minority are addressed, he will intensify the struggle for independence by next year. Velupillai Prabhakaran did not set an exact date in a speech on Sunday, but warned President Mahinda Rajapakse's hardline government that it must propose a framework that satisfied the political aspirations of the country's 3.2 million Tamils, who seek a homeland in the northeast. "If the new government rejects our urgent appeal, we will, next year, in solidarity with our people, intensify our struggle for self-determination, our struggle for national liberation to establish self-government in our homeland," he said. Prabhakaran was addressing the rebels on their annual "Heroes' Day" to pay homage to guerrillas killed while fighting government troops. Two days earlier, Rajapakse had rejected rebel demands for a homeland and promised to overhaul a 2002 ceasefire to curb violence and child recruitment by the Tigers.