Israeli Prime Minister Benjamin Netanyahu has said Israel will stick to its peace treaty with Egypt despite the attack on its embassy in Cairo.
He was speaking after protesters stormed the Israeli embassy on Friday, prompting the evacuation of nearly all Israeli diplomatic staff.
Egypt is on alert after the attack, in which three people died as security forces fought rioters in Cairo.
Cairo says those involved in the attack will be tried in an emergency court.
Anti-Israeli feeling rose after violence on the Gaza border last month.
Five Egyptian policemen were killed as Israeli forces pursued militants who had killed eight Israelis.
The US state department said it was "deeply concerned" about the attack on the Israeli embassy and relieved no staff had been injured.
Urging Egypt to safeguard the security of all foreign embassies on its territory, it stressed that both Israel and Egypt were "key partners and allies" of the US.
The clashes at the Israeli embassy, which carried on throughout Friday night, have shocked people both in Egypt and abroad, the BBC's Bethany Bell reports from the Egyptian capital.
"Israel will continue to hold fast to the peace accord with Egypt," Mr Netanyahu said in a televised address in Jerusalem.
"We are working together with the Egyptian government to return our ambassador to Cairo soon.
"I would like to ensure that the security arrangements necessary for him and for our staff will be steadfast."
The Israeli prime minister also thanked US President Barack Obama for American help to evacuate the embassy, without giving details.
"I would say it was a decisive moment - fateful, I would even say," he said.
"He [Mr Obama] said: 'I will do all that I can.' He did that. He applied all of the means and influence of the United States of America, which are certainly substantial."
Ambassador Yitzhak Levanon and nearly all other members of Israel's diplomatic team were evacuated from Egypt. Altogether more than 80 people - embassy staff, their families and security personnel - were flown out overnight to Israel.
Six members of the embassy security staff were trapped inside the building during the riot and had to be rescued by Egyptian commandos, an Israeli official told the BBC.
The Israeli consul remains in Cairo as acting ambassador.
Reports on Egyptian State TV said Prime Minister Essam Sharaf had offered to step down but his resignation was rejected by the country's military leader, Field Marshal Mohamad Hussain Tantawi.
Under Egypt's former leader, Hosni Mubarak, such violent displays of anger against Israel would not have been tolerated, our correspondent says.
Now the army has to try to balance the demands of its angry people and its longstanding strategic commitments, she adds.
Egyptian state media say at least 448 people were injured in the clashes overnight into Saturday.
The unrest began after Friday prayers, when thousands converged on Cairo's Tahrir Square to demand faster political reforms following the ousting of Mr Mubarak in February.
From there, hundreds marched on the Israeli embassy. They smashed through a security wall around the building before a group of about 30 broke in and threw documents out of windows.
An Israeli official told the BBC that the intruders had entered consular offices, but not the main embassy.
After initially standing by, police moved against the protesters, firing tear gas. Several vehicles were set alight.