Washington warned its Israeli ally against a ground invasion of Gaza, as the death toll from Israel's air campaign topped that of a 2012 assault and Cairo unveiled a truce plan Monday.
The announcement by Egypt, a mediator in past conflicts between Israel and the Palestinians, of a ceasefire to take effect at 0600 GMT on Tuesday came on the eve of a visit by US Secretary of State John Kerry in which he was expected to throw his weight behind peace efforts.
There was no immediate reaction from Israel.
Its Palestinian Islamist foe Hamas confirmed that efforts were under way to forge a truce like that which ended the last major Gaza conflict in 2012, but said no deal had yet been done.
The White House stopped short of criticising Israel over the civilian casualty toll from its devastating week-long air and artillery bombardment of the densely populated Palestinian enclave that has drawn flak from the United Nations and rights watchdogs.
It said the Israeli government had the "right" and "responsibility" to defend its citizens against rocket attacks by Hamas from its Gaza stronghold.
But it said even more civilians would be put at risk were Israeli Prime Minister Benjamin Netanyahu to heed hardliners in his governing coalition and send in troops and armour.
"Nobody wants to see a ground invasion because that would put more civilians at risk," White House spokesman Josh Earnest said.
It was the first time that the White House has specifically warned in a public forum against an Israeli invasion of Gaza, although other US officials, including Kerry, have previously said Washington would not like to see such a step.
With Israel's punishing air campaign in its seventh day, the death toll in Gaza hit 184, higher than the 177 people killed in the last major round of violence in and around Gaza in November 2012.
Egypt proposed that a ceasefire be followed by talks on easing the flow of goods into Gaza, which has long been heavily restricted by Israel.
"0600 GMT has been set for the beginning of the implementation of truce arrangements between the two sides," the text of the proposal read.
A Hamas official told AFP: "There are efforts and communications on the issue of a truce deal but until now there is nothing final."
Hamas has said that it wants to see Gaza's Rafah border crossing with Egypt -- the only one not controlled by Israel -- opened to the flow of goods.
Israel has said it is not ready to countenance a ceasefire, as it seeks to deal ever harsher blows to Hamas and stamp out its capacity to fire rockets deep into the Jewish state.
In a bid to add Washington's weight to truce efforts, Kerry is to fly into Cairo on Tuesday, Egyptian state media reported.
He is then expected to fly on to Qatar, a Western ally but one that maintains close relations with Hamas.
- Rising civilian toll -
In Gaza City's Tel al-Hawa neighbourhood, relatives of a retired economics professor in his 80s looked at the damage to his home, clearly bemused as to why it should have been targeted by an Israeli missile.
This time, the family escaped unharmed, fleeing after an initial warning strike. But the missile itself failed to explode, drawing a crowd of curious onlookers as officials wondered how to remove it.
Human rights groups say more than 75 percent of the dead have been non-combatants. The UN agency for Palestinian refugees says more than a quarter of them have been children.
Although Israel has confirmed preparations for a possible ground attack, it appeared to be holding off with the security cabinet meeting reportedly deciding against putting boots on the ground -- for now.
But the pace of the air strikes slowed noticeably on Monday.
Fourteen people were killed, fewer than the 56 killed on Saturday, the bloodiest day by far of a campaign which began before dawn on July 8 with the aim of halting militant rocket fire on southern Israel.
So far, no Israelis have been killed. Four have been seriously wounded.
The rocket fire has since intensified, with Hamas militants launching more than 800 rockets at cities across Israel, including Jerusalem, Tel Aviv and the northern city of Hadera.
A further 187 have been shot down by Israel's missile defences.
"The military steps being taken by both sides in the last 24 hours were a function, among other things, of the developments in the dialogue," Alex Fishman wrote in the top-selling Yediot Aharonot newspaper.
"If no catastrophe takes place that causes a particularly high number of fatalities on either side, the likelihood is that the fire will abate as early as this week."