In a telephone call on Sunday evening, Merkel and Israeli Prime Minister Ehud Olmert "agreed that the responsibility for the development of the situation in the region clearly and exclusively lies with Hamas," spokesman Thomas Steg told a regular government news conference.
"Hamas unilaterally broke the agreement for a ceasefire, there has been a continuous firing of ... rockets at Israeli settlements and Israeli territory, and without question - and this was stressed by the chancellor - Israel has the legitimate right to defend its own people and territory," Steg said. "As a result it is completely clear that in this situation Hamas is called upon to permanently stop the firing of rockets so that Israeli military operations can be ended quickly."
Merkel, however, told Olmert that "everything possible" must be done to avoid civilians being hurt by Israel's operations, Steg said. She believed long-term peace could only be arrived at through a political solution, he added.
The comments came as Israeli jets bombed Hamas targets in Gaza for a third day on Monday, killing several children, while the Islamists fired deadly rockets to retaliate for the blitz that according to medics has left more than 310 dead and more than 1,400 injured.
An Israeli Arab was killed and eight other people wounded when one of the projectiles slammed into a construction site in the southern city of Ashkelon some 13 kilometres (eight miles) north of the Gaza border.