A driving force behind the 1985 Live Aid appeal for Ethiopia, Geldof told a British radio station on Tuesday that Africa's debt problems stay a priority despite the Asian quake.
"The tsunami must be dealt with, it is an act of God, an act of nature," he told radio listeners, voicing concern the disaster would sideline chronic issues elsewhere.
But "Africa's an act of man. Millions die each year completely unnecessarily and that can be adjusted ... the issue is one of poverty and debt and it need not be," Geldof added.
He said the UK government should seize its chance to put Africa at the top of the world agenda with presidencies this year of the Group of Eight rich nations' club and of the European Union.