Washington's top diplomat flew into Tel Aviv Wednesday, defying a US flight ban, to try to broker an end to violence in Gaza, which has killed hundreds and hobbled Israel's main airport.
Secretary of State John Kerry jetted in from Cairo to Ben Gurion airport, with reporters banned from reporting the trip until his custom Boeing 757 touched down.
He was later to return to Tel Aviv for talks at the defense ministry with Israeli Prime Minister Binyamin Netanyahu, the official said, adding that Kerry had been engaged in phone calls with regional foreign ministers until the early hours of Wednesday.
Washington's top diplomat has urged all sides to embrace an Egyptian ceasefire initiative that would first halt the fighting before negotiations.
The truce was accepted by Israel but rejected by Hamas, the de facto power in Gaza, which has laid down a series of conditions, including a removal of Israel's eight-year blockade on the enclave.
The United States has repeatedly supported Israel's Operation Protective Edge as self-defense as Hamas showers its ally with rockets.
But President Barack Obama and Kerry have also voiced growing concerns about the costs to civilians, including the deaths of numerous Palestinian children.
Kerry, who has invested much of his tenure into an unsuccessful bid to reach a permanent Israeli-Palestinian peace agreement, has backed the Egyptian truce proposal but is looking for ways to find the quickest possible end to the violence.
"While we still have work to do, it is clear to each party I met that there is a framework available to end the violence, and that framework was the Egyptian initiative," Kerry said Tuesday in Cairo after meeting Egypt's President Abdel Fattah al-Sisi, a former army chief who has a frosty relationship with Hamas.
Kerry has walked a delicate line, with a US official saying that the Egyptian plan offered "the frame and forum for discussions" but that "there are a range of options under consideration for a ceasefire."
Kerry, in an unguarded moment caught Sunday between televised interviews, appeared to voice concern that Israel would escalate its campaign after soldiers' deaths, saying, "I hope they don't think that's an invitation to go do more."
Kerry's arrival in Israel came a day after the US Federal Aviation Administration banned US carriers from flying into Tel Aviv for 24 hours following a Hamas rocket that landed close to Ben Gurion airport.
Netanyahu appealed to Kerry by telephone late Tuesday to lift the ban, which is the first since the 1990-1991 Iraq war when Saddam Hussein's regime lobbed missiles at Israel.
Kerry insisted it was imposed solely in the interest of protecting US carriers and travellers, not as a negotiating tactic.
"The only consideration in issuing the notice was the safety and security of our citizens," State Department spokeswoman Jen Psaki said.
Major US and European carriers suspended their services after the rocket struck.
A prolonged airport closure would likely pose risks to Israel's economy, which has largely been spared the impact of frequent conflict in the region.