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UN Secretary General Antonio Guterres on Monday warned the humanitarian situation in the Gaza Strip would collapse as Israel responds to the Hamas attacks.
Israeli Defence Minister Yoav Gallant had earlier ordered a “complete siege” of Gaza, saying authorities would cut electricity and block the entry of food and fuel.
“The humanitarian situation in Gaza was extremely dire before these hostilities,” the UN chief said in New York. "Now it will only deteriorate exponentially.
He called for the protection of civilians and for Israeli military operations to be conducted in strict accordance with international humanitarian law.
Mr Guterres condemned the “abhorrent attacks by Hamas” in Israel, which have left more than 900 Israelis dead and more than 2,500 injured.
“Nothing can justify these acts of terror and the killing, maiming and abduction of civilians,” he said, repeating his call for an immediate cessation of violence and the release of all hostages.
He also expressed alarm by reports of more than 500 Palestinians – including women and children – killed in Gaza and more than 3,000 injured.
“Some 137,000 people are currently sheltering in UNRWA facilities – with the number increasing as heavy shelling and air strikes continue,” he said, referring to the UN Relief and Works Agency.
He urged all sides and the relevant parties to allow the UN access to deliver urgent humanitarian assistance to Palestinian civilians trapped and helpless in the Gaza Strip.