Pope Francis speaking to members of the government of the Holy See Saturday condemned Israel's bombing of children in Gaza as "cruelty."
The pontiff's remarks came a day after an Israeli airstrike had killed seven children from one family.
"Yesterday they did not allow the Patriarch (of Jerusalem) into Gaza as promised," the pope said.
"Yesterday children were bombed. This is cruelty, this is not war.
"I want to say it because it touches my heart."
The criticism was, however, met with a sharp response from Israel which accused him of double standards.
In a statement, an Israeli Foreign Ministry spokesman described the pope's remarks as "particularly disappointing as they are disconnected from the true and factual context of Israel's fight ... a multi-front war that was forced upon it starting on October 7."
"Enough with the double standards and the singling out of the Jewish state and its people," he added.
Earlier Friday, Gaza's civil defense rescue agency reported that an Israeli airstrike had killed 10 members of a family in the northern part of the territory, including seven children.
Francis, 88, has called for peace since the war started. In recent weeks, he has hardened his remarks against the Israeli offensive.
In late November he said "the invader's arrogance ... prevails over dialogue" in "Palestine," a rare position that contrasts with the tradition of neutrality of the Holy See.
In a recently published book the pope called for a "careful" study as to whether the situation in Gaza "corresponds to the technical definition" of genocide, an accusation rejected by Israel.
Since 2013, the Holy See has recognized the State of Palestine, with which it maintains diplomatic relations and supports the two-state solution.
The latest war was triggered by the Hamas incursion of Israel on Oct. 7, 2023, which caused 1,208 deaths and took 251 hostages, of whom 96 remain in Gaza, including 34 the Israeli military says are dead.
Israel's genocidal war, in contrast, has killed at least 45,206 people, mostly women and children, according to the territory's Health Ministry.