Israeli PM Benjamin Netanyahu said a proposal for a new Gaza ceasefire is "far from Israel's basic requirements" but negotiations will continue.
His comments came after Hamas said it had accepted the truce terms offered by Qatari and Egyptian mediators.
"The ball is now in Israel's court," an official in the Palestinian group said.
Overnight, Israeli forces and tanks were seen near the Rafah border crossing in southern Gaza, reports in Israeli media said.
Earlier, Israel's military carried out air strikes on Rafah, on the border with Egypt, after warning Palestinians to evacuate eastern parts of the city.
Tens of thousands of residents are believed to be affected by the operation and many were seen cramming into vehicles or on to donkey carts on Monday.
