The UN has suspended its aid operations in Gaza "until the Israeli authorities can guarantee their safety and security", the organisation has said.
A spokesperson from The United Nations Relief and Workers Agency (UNRWA) said the decision was taken after an aid worker was killed, and two others injured, by tank fire, while crossing the Israeli border with aid deliveries.
"Our installations have been hit, our workers have been killed in spite of the fact that the Israeli authorities have the co-ordinates of our facilities and that all our movements are co-ordinated with the Israeli army."
UNRWA has stated that full operations will resume once the orgnaisation has received a guarantee of workers' safety.
Israeli government spokesman Mark Regev stated today that Israel is fully behind the work of the UN in Gaza.
"We will do what needs to be done to facilitate this vital work. In these difficult days we must work together to meet the humanitarian needs of the population."
The UN Secretary General Ban Ki-Moon has condemned the actions of the Israeli Defence Force (IDF).
In a statement, he said, "The secretary-general calls once again for an immediate ceasefire in order to facilitate full and unhindered humanitarian access, and to allow aid workers to work in safety to reach persons in need."
The IDF has not commented on the incident but claims to be looking into the matter.