Israel bombed areas of Jabalia in the northern Gaza Strip overnight, with fighting throughout on Sunday, residents and Palestinian media said, as Gaza health authorities and the Israeli military both announced mounting death tolls.
Meanwhile, a Gaza health ministry spokesman said on Sunday that 166 Palestinians had been killed in the past 24 hours, taking the total Palestinian death toll to 20,424.
Tens of thousands have been wounded, with many bodies believed trapped under rubble. Almost all of Gaza's 2.3 million people have been displaced.
The number of Palestinian journalists died after the start of the new round of escalation in the Palestinian-Israeli conflict reached 100, the Al Jazeera reported.
Israeli forces have killed some 8,000 Palestinian fighters in the Gaza war, a military spokesperson said on Sunday, adding that the figure was drawn from accounts of targeted strikes and battlefield tallies as well as the interrogations of captives.
Israel says it has achieved almost complete operational control over northern Gaza and is preparing to expand a ground offensive against Hamas fighters to other areas.
But Jabalia residents reported persistent aerial bombardment and shelling from Israeli tanks, which they said had moved further into the town on Saturday.
"This is a difficult morning, after a very difficult day of fighting in Gaza," Prime Minister Benjamin Netanyahu said at a cabinet meeting on Sunday.
The White House said on Saturday US President Joe Biden and Netanyahu had discussed the Israeli campaign.
Biden "emphasized the critical need to protect the civilian population including those supporting the humanitarian aid operation, and the importance of allowing civilians to move safely away from areas of ongoing fighting," the White House said in a statement.
Egyptian and Qatari mediators have been trying to break the deadlock to end the violence. A delegation of the Palestinian Islamic Jihad group, which also has captives in custody in Gaza, arrived in Cairo for talks with Egyptian officials over "ways to end the Israeli aggression on our people in Gaza," an official of the group told Reuters.
Netanyahu, speaking at a weekly cabinet meeting on Sunday, dismissed reports that the United States had convinced Israel not to expand its military campaign.
The UNSC averted a threatened US veto on Friday, after days of wrangling, by removing from a draft resolution a call for an immediate end to the war. The US and Israel oppose a ceasefire, contending it would let Iran-backed Hamas regroup and rearm.
Washington abstained from the final statement, which urges steps to allow "safe, unhindered, and expanded humanitarian access" to Gaza and "conditions for a sustainable cessation" of fighting.