Destroyed buildings in the Gaza Strip are pictured from a position along Israel's southern border with the besieged Palestinian territory
A widening of the war "would risk catastrophic consequences for millions of Palestinians and could further endanger the lives of the remaining hostages in Gaza," Miroslav Jenca, UN assistant secretary-general for Europe, Central Asia and the Americas, told a Security Council meeting.
"There is no military solution to the conflict in Gaza or the broader Israeli-Palestinian conflict," Jenca said.
During a visit to an army training facility earlier on Tuesday, Netanyahu said: "It is necessary to complete the defeat of the enemy in Gaza, to free all our hostages and to ensure that Gaza will no longer pose a threat to Israel."
Israeli media said the premier was considering ordering the total occupation of the Palestinian territory, with public broadcaster Kan reporting that "Netanyahu wants the Israeli army to conquer the entire Gaza Strip."
Netanyahu's office said he held a three-hour "security discussion" on Tuesday with army chief Eyal Zamir, but did not disclose any new war plans.
The premier's office earlier said the army was prepared to implement any decision made by the security cabinet, which is due to convene later in the week to approve new instructions.
Citing cabinet members, Kan reported that Netanyahu had "decided to extend the fight to areas where hostages might be held" inside Gaza.
But some major media outlets such as Channel 12 have suggested that the rumoured expansion of military operations may only be a negotiating tactic.
Over the 22 months of war, Israeli forces have devastated large parts of the Gaza Strip, where repeated warnings of famine have increased pressure on Netanyahu's government to halt the fighting.
The Israeli war on Gaza has killed at least 61,020 Palestinians, mostly women and children.
*The story was edited by Ahram Online
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