RNA - Mladenov gave the warning while addressing the UN Security Council on Wednesday, where he called for urgent action to relieve the suffering of Gaza's "increasingly desperate" people, Palinfo reported.
He added that people of Gaza were living with "crippling Israeli closures and with diminishing hopes for an end to the occupation and a political solution".
"Gaza's infrastructure teeters on the verge of total collapse, particularly its electricity and water networks as well as its health system," he said.
Mladenov further called on the international community to join "in condemning in the strongest possible terms the actions that have led to the loss of so many lives in Gaza" since March.
Israeli forces killed 65 Palestinians during rallies near the Gaza fence on the eve of the 70th anniversary of the Nakba Day, which coincided with Washington’s embassy relocation from Tel Aviv to Occupied Jerusalem. More than 3,000 Palestinians were also wounded by Israeli gunfire during that day.
The UN official also denounced Israeli settlement activities in the occupied West Bank and Israel’s destruction of dozens of Palestinian homes and structures recently.
According to him, Israeli authorities have demolished or seized some 30 Palestinian-owned structures across the West Bank, including East Jerusalem. As a result, 43 Palestinians have been displaced and the livelihoods of over 140 have been affected.