Israel hit 200 sites overnight, including PM Ismail Haniya’s office.
Gaza militants fired dozens of rockets into Israel, including one at the city of Tel Aviv that was intercepted Israel’s military says by a newly installed battery of its Iron Dome defence system.
At least 42 Palestinians and three Israelis have now died since Israel killed the Hamas military chief Ahmed Jabari on Wednesday.
Israel has 75,000 reservists on stand-by, on top of the 16,000 called up
in recent days.
Hamas has confirmed Mr Meshaal will meet the Emir of Qatar, Egypt’s President Mohammed Mursi and Turkey’s President Recep Tayyip Erdogan in Cairo on Saturday night to discuss how a ceasefire can be achieved.
Ahead of the meeting, Mr Erdogan said: “It’s a tactic of Israel’s to point the finger at Hamas and attack Gaza.
“Israel continues to make an international racket with its three dead. In fact it is Israel that violated the ceasefire.”
Palestinian Authority President Mahmoud Abbas has accused Israel of carrying out “massacres”.
Tunisian Foreign Minister Rafik Abdessalem arrived in Gaza through the Rafah border crossing from Egypt to show support for Hamas. Later on Saturday he visited the wreckage of Mr Haniya’s HQ.