GAZA/JERUSALEM — Israel said on Sunday it was prepared for protracted military action in Gaza and would not negotiate under rocket fire as Egypt crafted a new truce plan to try to keep indirect Israeli-Palestinian talks alive.

Since a three-day truce expired on Friday, Palestinian rocket and mortar salvoes have focused on Israeli kibbutzim, or collective farms, just across the border in what appeared to be a strategy of sapping the Jewish state's morale without triggering another ground invasion of the Gaza Strip.

An Egyptian Foreign Ministry source said a new 72-hour ceasefire plan was still being crafted and it was too early to say if a deal would result.

In Tel Aviv earlier, Prime Minister Benjamin Netanyahu said "Israel will not negotiate under fire".

"At no stage did we declare (Israel's military offensive) was over," he said. "The operation will continue until its objective — the restoration of quiet over a protracted period — is achieved," he said in public remarks at the weekly cabinet meeting. "I said at the beginning and throughout the operation — it will take time, and stamina is required."

Egypt is meeting separately with each party, given that Hamas, the dominant movement in Gaza, rejects Israel's right to exist and Israel and most of the world regard the group as a terrorist organization.

Israel has resisted easing access to Gaza, suspecting Hamas could then restock with weapons from abroad.

A sticking point has been Israel's demand for guarantees that Hamas would not use any reconstruction supplies sent to Gaza to build more tunnels of the sort that Palestinian fighters have used to infiltrate the Jewish state.

Israeli tanks and infantry left the enclave on Tuesday after the army said it had completed its main mission of destroying more than 30 tunnels dug by guerrillas for cross-border attacks.

Some said on Sunday they would not return to their communities, which have long been symbols of Israel's pioneering spirit — an abandonment likely to raise pressure on Netanyahu.

"I heard the prime minister's various speeches, but we see the reality of the situation here," Yossi Wagner, a member of the skeletal security team at Kibbutz Nahal Oz, told Israel's Army Radio. "We have decided that at this stage we are not recommending that members return to the kibbutz."