Moves by Palestinian President Mahmud Abbas to seal reconciliation with Hamas drew an angry response in Israel on Friday, with one government minister even calling for the annexation of settlements in the West Bank.
After talks with Abbas in Cairo on Thurday that Hamas leader Khaled Meshaal told AFP were held in an "excellent atmosphere," the two men agreed on a process that would pave the way for the Islamist group to join a reformed Palestine Liberation Organisation and for long delayed Palestinian elections.
Israeli Prime Minister Benjamin Netanyahu's spokesman, Mark Regev, said the deal with the Islamist rulers of Gaza was proof that the Palestinian president was not interested in peace.
"Hamas is not a political movement that resorts to terrorism but a group hose whole vocation is terrorism," Regev told AFP.
"The closer President Abbas moves to Hamas, the further he moves away from peace."
Transport Minister Israel Katz, from Netanyahu's Likud party, said Israel should respond by unilaterally annexing settlements in the West Bank.
"Israel must impose its sovereignty on all Jewish districts of Judaea and Samaria (the West Bank)," Katz told public radio.
"Israel must also make preparations to ensure the safety of its citizens in the face of this terrorist organisation backed by Iran," he added.
"Finally, we need to take the necessary steps to ensure that the Jewish population (of the West Bank) has ready access to all corners of the state of Israel.
"This alarming rapprochement between Abu Mazen (Abbas) and Hamas is aimed at forming a government that one can only say is aimed at bringing about a genocide," he charged.
"Since the dark days of Nazism, no other movement has set as its aim the killing of Jews."
Israel has expressed mounting alarm as Abbas's secular Fatah faction has intensified efforts to reconcile with Islamist Hamas in recent weeks.
Abbas and Meshaal have met three times in the past month to thrash out implementation of a surprise deal they signed in May.
The two factions had previously been at loggerheads ever since Hamas seized control of Gaza in 2007, leaving the Palestinian territories with rival administrations.