At least 26 people have died in the Gaza Strip as Israeli forces kept up air strikes they say are aimed at stopping rocket attacks into Israel.
Fewer rockets have been launched, but Israeli towns are still being hit.
Ninety-five Palestinians and three Israelis have died in six days of violence, the latest including a militant group commander, the BBC reports.
Efforts to secure a ceasefire continue, with a senior Egyptian official saying there are "encouraging signs".
Khaled Meshaal, the political leader of the Islamist movement Hamas which controls Gaza, said Israeli Prime Minister Benjamin Netanyahu had requested a ceasefire but that it was up to Israel to stop the war that, he said, it had started.
Israel immediately denied making any such request, Reuters news agency reported.
Mr Meshaal said that a truce was possible in Gaza, as was further escalation of the conflict. Morale in Gaza was high and anyone who attacked the Palestinians would be "buried".
Egyptian President Mohammed Mursi has said an Israeli ground invasion would have "serious repercussions", saying Egypt would never accept it "and neither will the free world".
Mr Netanyahu said on Sunday that he was ready to expand the operation, after Israel authorised the mobilisation of up to 75,000 army reservists.
The Israel Defense Forces said they targeted about 80 sites overnight into Monday alone, including militant-owned buildings, weapons storage facilities and police stations, bringing its total to 1350 sites targeted since last Wednesday when the violence began following the killing of Hamas military chief Ahmed Jabari.