“France calls for an immediate ceasefire…to ensure that every side starts talking to each other to avoid an escalation that would be tragic for this part of the world,” said Defence Minister Jean-Yves Le Drian in a television interview.
Israel started its military offense on Tuesday in a bid to stop cross-border rocket fire by militant groups.
France's Foreign Minister Laurent Fabius also addressed the conflict's escalation on Sunday while in Vienna during a meeting with his Western counterparts to discuss Iran's nuclear programme.
"In Gaza, like in Israel, the priority is a ceasefire. In this context, of an absolutely disastrous escalation, France -- like the UN Security Council -- calls for a return to the truce of 2012," Fabius said, referring to a ceasefire that brought fighting to an end between Israel and Hamas militants in November 2012.
The Israeli military said it had struck 1,320 “terror targets” across Gaza by Sunday morning.
More than 650 rockets have rained down on Israel since Tuesday, while another 170 have been diverted by its Iron Dome missile defence system, according to the army.
There have been no Israeli fatalities, and two people have been badly injured.
On Sunday, Israeli strikes on Gaza killed a teenage boy and a woman, raising the overall death toll to 165.
One strike on the northern town of Jabaliya struck a house, killing a 14-year-old boy, according to emergency services spokesman Ashraf al-Qudra.
Another strike killed a woman shortly after in the Maghazi refugee camp in central Gaza.
Saturday amounted to the bloodiest day of the offense, killing 52 people.
In a phone call with Palestinian president Mahmud Abbas, French President François Hollande condemned the civilian deaths by rocket fire and called on Palestinians and Israelis to swiftly reach a lasting peace agreement.