Israel opposes a mass return of the Palestinians, fearing it would dilute the state's Jewish majority.
Israel has offered to take in a small number of Palestinian refugees but insists that the rest must be resettled in a future Palestinian state to be created under a peace accord or in the countries where they now live.
In the Palestinian public discourse, a large-scale return is still portrayed as the main goal. The Palestinian leadership has said each refugee has the right to choose his or her fate, including return or resettlement in a state of Palestine or third countries, but also hinted at flexibility in the context of a final deal.
"It is time for the leaders of Israel to understand that there is no homeland for the Palestinians except Palestine, and it is here we are staying," Palestinian President Mahmoud Abbas said in his Nakba Day address broadcast Wednesday night.
"It is time to end the longest occupation in modern history," Abbas added.
For their part, the Palestinians have been split since 2007, when Islamic Hamas militants seized control of Gaza from forces loyal to the secular, Western-backed Abbas. Hamas now rules Gaza while Abbas and the Palestinian Authority have control of parts of the West Bank.
The two Palestinian factions have made significant reconciliation gestures recently and seem to be closer to bridging their differences.
In his address, Abbas said that ending the division is a top Palestinian priority.