JERUSALEM - Israel vowed no let-up in its aerial bombardment of Gaza, which has claimed more than 100 Palestinian lives, as a defiant Hamas rained more rockets on the Jewish state.
Diplomatic efforts to end the hostilities have gathered pace, with US President Barack Obama phoning Israeli Prime Minister Benjamin Netanyahu and Washington offering to use its relationships in the Middle East to help end the hostilities.
Speaking at a news conference Friday in Tel Aviv, Netanyahu said he would not end the military campaign until he achieved his goal of stopping the Hamas fire.
"No international pressure will prevent us from striking, with all force, against the terrorist organisation which calls for our destruction," he said.
"No terrorist target in Gaza is immune."
Despite international concerns, truce efforts have been unsuccessful, according to Cairo, which has been key in mediating previous Hamas-Israel ceasefires.
"Egypt has communicated with all sides to halt violence against civilians and called on them to continue with the truce agreement signed in November 2012," the foreign ministry said.
"Unfortunately, these efforts... have met with stubbornness."
After weeks of rocket fire into its southern flank, Israel appeared bent on dealing a fatal blow to the Gaza-based Islamist Hamas.
Ismail Haniya, Gaza's former premier and the most senior Hamas official in the coastal enclave, also ruled out any end to hostilities.
"(Israel) is the one that started this aggression and it must stop, because we are (simply) defending ourselves," he said.
Ground attack decision soon
Israel says preparations are under way for a possible ground attack, with tanks and artillery massed along the border and some 33,000 reservists mobilised out of 40,000 approved by the cabinet.
Foreign Minister Avigdor Lieberman said on Friday he expected a political decision on a possible ground operation within 48 hours.
"At the moment we are dealing with the first phase... air attacks," he told Channel One television.
"I imagine we shall decide tomorrow (Saturday) or the day after on the next stage."
Hamas's armed wing, the Ezzedine al-Qassam Brigades, kept up a steady stream of rocket fire on Israel throughout Friday.
Five rockets were shot down over Tel Aviv by the Iron Dome anti-missile system, the army said.
The Brigades said their militants had targeted Israel's main international airport near the city.
Early Saturday 16 Palestinians died in a wave of Israeli air strikes as Operation Protective Edge entered its fifth day, hiking the overall death toll to 121, medics said.
The Israeli military said in a statement that it had struck "several terrorists conspiring to launch rockets at Israel," but did not elaborate.
So far, no one in Israel has been killed. Two have been seriously wounded, including a man at a petrol station hit by a rocket.
In northern Israel, at least one rocket fired from Lebanon struck an open area near the town of Metula, prompting troops to hit back with artillery fire, the army said.
The military believed a Palestinian group had fired in solidarity with Hamas, public radio reported.