The Pope, who travelled to Cameroon and Angola this month, noted that South Africa would be the continent’s only nation represented at the Group of Twenty meeting on Thursday.
"This situation must prompt a profound reflection among the summit participants, since those whose voice has least force in the political scene are precisely those who suffer most from the harmful effects of a crisis for which they do not bear responsibility," the pontiff said.
He said it was necessary to turn to the multilateralism of the United Nations and related organisations "in order to hear the voices of all countries and to ensure that measures and steps taken at G20 meetings are supported by all".
The pope said the economic downturn had raised the threat of the cancellation of or drastic reduction in aid programmes, especially for Africa — which he said was not the cause of the crisis and should not become its victim.
He said "solutions marked by any nationalistic selfishness or protectionism" must be avoided to find a way out of the crisis.