A senior official on Tuesday confirmed that Israel transferred the bodies of 45 Palestinians to the Gaza Strip.
Israel controls access to the Gaza Strip and has to authorise aid deliveries to the sealed-off territory.
Israel has prohibited UNRWA from operating in the Gaza Strip since January.
The political leadership has ordered that “humanitarian aid continues to enter the Gaza Strip through the Kerem Shalom Crossing.
Mr Guterres, on X, said he was “profoundly relieved” that the individuals, who had endured “immense suffering,” had regained their freedom.
The first buses carrying those released left Ofer Prison on Monday in the West Bank near Jerusalem, headed for Ramallah.
The current round of indirect ceasefire talks between Hamas and Israel, mediated by Egypt and Qatar, began Monday in Sharm el-Sheikh, Egypt.
Mr Al-Sissi thanked Mr Trump in a televised speech on Monday for helping to initiate a ceasefire after “two years of war, genocide, killing, and destruction.”
The deal, unveiled at the White House on Monday by Mr Trump and Israeli Prime Minister Benjamin Netanyahu, sets out a 20-point framework.
“We are here, and we won’t move from here,” said Ofir Braslavski, father of Rom Braslavski, who also holds German citizenship.
