RAMALLAH, May 15 (Xinhua) -- Palestinian President Mahmoud Abbas warned Friday that the Israel-Hamas ceasefire in Gaza remains "fragile" as casualties mount, territory shrinks, and humanitarian aid faces persistent obstruction.

"The ceasefire remains fragile while our people continue to be killed, Gaza's geography is shrinking, and aid continues to face obstruction in clear Israeli violation," Abbas said in a speech delivered on his behalf by Palestine's Permanent Observer to the United Nations Riyad Mansour.

The speech was delivered at a UN event in New York marking the 78th anniversary of the Palestinian "Nakba," the mass displacement of Palestinians following the establishment of the state of Israel in 1948, observed annually on May 15.

Abbas said in the speech that the Palestinian leadership is working with mediators and partners to move toward the second phase of the ceasefire agreement to begin recovery and reconstruction efforts.

He reiterated the Palestinian vision of "one state, one government, one law and one weapon," and stressed the need for a full Israeli withdrawal from the Gaza Strip.

Palestinians accuse Israel of recreating the Nakba through its war in Gaza, which they say has killed more than 72,000 people, caused massive destruction to residential buildings and obstructed the work of the UN Relief and Works Agency for Palestine Refugees in the Near East. ■