Israel is seeking to resume diplomatic relations with Egypt after protesters stormed Israel’s embassy in Cairo, trashing offices and prompting the evacuation of nearly the entire staff from Egypt in the worst crisis between the countries since their 1979 peace treaty.

Israel said on Sunday that Ambassador Yitzhak Levanon and his staff will return if security assurances are met.

"The security in front of the embassy has been enhanced," cabinet spokesman Mohamed Higazy told Reuters. "Returning back to normalcy is the objective for both sides."

The U.S. State Department expressed concern about the violent protests and said Saturday it would do all it can to support the relationship between the two countries.

“Israel and Egypt are key partners and allies of the United States, and both states have made clear their continuing commitment to maintain their bilateral relationship and the peace treaty between them, which remains a cornerstone of regional stability,” State Department spokeswoman Victoria Nuland said in a statement, adding that Secretary of State Hillary Clinton has spoken to both Israeli and Egyptian officials about the incident.

“We underscore the need for the Egyptian Government to meet its obligations under the Vienna Conventions to safeguard the security of all foreign missions in Egypt,” she said.

The 13-hour rampage deepened Israel's fears that it is growing increasingly isolated amid the Arab world's uprisings and, in particular, that Egypt is turning steadily against it after the fall of Hosni Mubarak, the authoritarian leader who was a close ally.

In Israelis' eyes, the scene of cars burning outside the embassy and the tale of six Israeli guards trapped inside for hours in a steel-doored safe room underscored their view that anti-Israeli sentiment in Egypt was running free after decades of being contained by Mubarak's regime. The ousted leader's powerful security forces never would have let a protest get near the Nile-side embassy.

Egypt's new military rulers, in turn, appear caught between preserving key ties with Israel -- which guarantee them billions in U.S. military aid -- and pressure from the Egyptian public. Many Egyptians are demanding an end to what they see as too cozy a relationship under Mubarak, who they feel knuckled under to Israel and the U.S., doing nothing to pressure for concessions to the Palestinians.

Egyptian security forces did nothing as hundreds of protesters massed Friday outside the Nile-side high-rise residential building where the Israeli Embassy is located and tore down a concrete security wall Egyptian authorities erected there only weeks earlier. Many protesters saw the wall as a symbol of the government's willingness to protect Israelis but not Egyptians, since it was put up to keep back protests after Israeli forces chasing militants accidentally killed five Egyptian soldiers in the Sinai Peninsula.

Police and military also did little initially when a group of around 30 protesters after nightfall climbed in a third-story window and raced up to the embassy floors, broke into an office and began throwing Hebrew-language documents to the crowd below. The protesters ransacked parts of two floors of the embassy for hours until police finally managed to clear them out in the early hours Saturday.

Frantic Israeli calls to President Obama brought American intercession to help ease the violence.

An Egyptian security official said the ruling military did not order the police to clamp down on the protests outside in order to "avoid a massacre." They couldn't move more quickly to clear out protesters inside the embassy because the fervent crowd outside "considered them heroes," he said, speaking on condition of anonymity because he wasn't authorized to talk to the press.

But in a Saturday evening television address, Israeli Prime Minister Benjamin Netanyahu avoided any condemnations and instead stressed the need to maintain strategic relationship with Egypt, whose peace with Israel -- though sometimes chilly -- has been a vital peg of stability for the Jewish state.

"We will continue to keep the peace with Egypt it is an interest of both countries," Netanyahu said.

From the Egyptian side, the ruling military council and civilian government underlined in a statement read on state TV that Egypt is committed to international conventions and the protection of diplomatic missions.

They also vowed to crack down on future protests at the embassy, warning that Egypt was experiencing a "real predicament that threatens the very body of the state that requires decisive actions." To "safeguard the state," they said they would re-invigorate parts of hated emergency laws, which for months the military has promised to abolish in a concession to demands for reform.

The deterioration with Egypt comes as Israel has also been hit by a major downturn in ties with longtime ally Turkey. After Israel refused to apologize for its deadly raid on a Gaza-bound aid flotilla last year that killed eight Turks and a Turkish-American, Turkey expelled several senior Israeli diplomats, suspended military cooperation with Israel and boosted naval patrols in the eastern Mediterranean in response.

Israel is also feeling the heat from Palestinian plans to unilaterally seek recognition of an independent state at the United Nations this month amid a long stalemate in the peace process. Israelis also fear that the Arab spring could bring rising influence to Islamic fundamentalists in the region.

The Associated Press contributed to this story.