Israel's defence minister warns the war with Hamas could last "several" more months while the PM again vows "absolute victory".
Israel has reportedly also told US officials that the current intensive phase of the conflict could be finished in a matter of two or three weeks.
US President Joe Biden has urged Israel to be more focused on how to save civilian lives in Gaza.
The ground incursion into Khan Younis, Gaza's second city, entered a critical stage on Thursday as Israel pounded the centre.
Internet and phone networks across Gaza again went down on Thursday, according to the region's main telecoms company.
Hamas broke through Israel's heavily guarded perimeter on 7 October, killing 1,200 people and taking 240 hostages - some of whom were released during a brief truce.
The health ministry in Gaza, which is run by Hamas, says more than 18,700 people have been killed and 50,000 injured in the enclave since the start of the Gaza war.