"Do we really wan to live in a world where the 1 percent own more than the rest of us combined? The scale of global inequality is quite simply staggering and despite the issues shooting up the global agenda, the gap between the richest and the rest is widening fast," Oxfam's Byanyima said in a statement.
"In the past 12 months we have seen world leaders from President (Barack) Obama to (International Monetary Fund Managing Director) Christine Lagarde talk more about tackling extreme inequality but we are still waiting for many of them to walk the walk."
Measures that Oxfam is calling for to tackle inequality include a clamp down on tax dodging by firms and wealthy individuals, and investment in free, universal public services such as health and education.
"Sadly, there are still billions of people who live in poor countries with dysfunctional economies," Ryan Bourne, head of public policy at the London-based Institute of Economic Affairs, said in a statement following the publication of Oxfam's report.
"Rather than focusing on the top 1 percent we should be promoting policies such as free trade, open markets, stable property rights, and the elimination of corruption that can ensure that many other countries can replicate the Asian growth miracle."