Palestinian officials in Gaza say Sunday was the deadliest day since the current fighting with Israel began.
Forty-two people were killed in Israeli air strikes on the territory.
Israel’s army say Palestinian militants have fired more than 3,000 rockets at Israel over the past week.
United Nations Secretary-General António Guterres has warned that further fighting could plunge the region into an “uncontainable crisis”.
He pleaded for an immediate end to the “utterly appalling” violence.
Early today, Israeli warplanes launched 80 air strikes on several areas of Gaza City, shortly after Hamas militants fired a barrage of rockets at southern Israel.
Lynn Hastings, UN deputy special co-ordinator for the Middle East Peace Process, told the BBC that she had appealed to Israeli authorities to allow the UN to bring in fuel and supplies but was told it was not safe.
The overall death toll in Gaza now stands at 197 people, including 58 children and 34 women, with 1,230 injured, according to the Hamas-controlled health ministry. Israel says dozens of militants are among the dead.
