Richard Falk, a U.N. special envoy appointed to address human rights issues in the Palestinian territories, said following a weeklong visit to the region that he saw evidence to suggest Israeli forces may have deliberately attacked civilian targets.
"It is clear that some attacks killed and harmed civilians in a grossly disproportionate manner and thus appear to violate international law," he said in a statement from Cairo.
The U.S. government stood by Israel during the November offensive. Both sides stressed that Israel has a right to defend itself from rocket attacks emanating from Hamas-controlled territory in Gaza.
The U.N. General Assembly, in a late November vote, backed a resolution that gave Palestinians more recognition at the world body. Palestinian negotiators said the move would help facilitate the peace process, though the Israeli and U.S. governments said the resolution was an obstacle.
Israel was criticized recently for moving ahead with plans to extend settlement activity in Palestinian territory. The Jerusalem Post reports Wednesday the European Union summoned the Israeli ambassador to address settlement concerns.