Ismail Haniyeh spoke only hours after Hamas militants held a press conference in the nearby Jabaliya refugee camp saying they would continue firing rockets at Israel and that they would target the port city of Ashkelon.

"Our sons will stop the firing of Qassam rockets as a means of defense if the Israeli occupier ceases its aggressive incursion and its occupation in the north of the Gaza Strip," said a statement by Haniyeh.

Earlier, a leader of the Hamas military wing, the Ezzedin al-Qassam Brigades, told the press conference that "the Israeli military operation has failed," a reference to a campaign to stop the rockets that has left more than 50 Palestinians dead this week.

"We will continue to fire Qassam rockets, and we call on the residents of Ashkelon to leave their homes."

On August 28, Hamas fired a Qassam rocket from northern Gaza into an industrial zone of Ashkelon, which lies on the Mediterranean coast just a little over 10km north of the Gaza.

No one was hurt by the rocket, which struck in wasteland near a brewery and was the first improvised device to penetrate so far into Israel.