"The truce is based on conditions and the conditions have not been met yet by Israel, and there are no indications that the conditions will be met," al-Zahar told reporters in Gaza.
He said: "This is why Hamas holds contacts with the Egyptian side and the parties that sponsored the Palestinian dialogue held in Cairo last month," which reached a cease-fire agreement.
"If conditions are not met, we will be free from any commitment and we will strike against Israel with all means," said al-Zahar. "This is what we translated on the ground when three Palestinian children were killed in Rafah last week."
Hamas fired dozens of homemade mortar shells at Jewish settlements in Gaza after the three were killed by Israeli soldiers near the borderline between Gaza and Egypt. Israeli forces said the youths, who reportedly were playing soccer, were in an off-limits area and were smuggling.