JERUSALEM, Jan. 29 (JTA) — After the shock of Hamas’ sweep in the Palestinian Authority parliamentary elections, Israel is preparing for a diplomatic lull.

Acting Prime Minister Ehud Olmert, having already ruled out negotiations with a government run by the Islamic terrorist group, on Sunday broadened the boycott to include all of the Palestinian Authority.

“Israel will not hold any contacts with the Palestinians,” Olmert told his Cabinet, unless Hamas recognizes the Jewish state’s right to exist, abandons violence and accepts previous peace accords.

Hamas took more than half of seats in the Palestinian Legislative Council in the Jan. 25 vote, prompting the long-dominant Fatah faction to bring down the government. Fatah has so far ignored appeals by Hamas to run the Palestinian Authority together, raising the prospect of an Islamic theocracy taking form in the West Bank and Gaza Strip, increasingly isolated from the West.

With Hamas and Fatah gunmen already in skirmishes, and a terrorist “truce” against Israel in jeopardy, a new flare-up of violence looms. The Hamas leader in exile, Khaled Meshaal, stoked the flames of speculation by proposing that his group form a full-fledged Palestinian army.

Israeli Defense Minister Shaul Mofaz warned Hamas it would incur a massive military onslaught if it resumed suicide bombings after an almost yearlong lull.

“If Hamas carries out terrorist attacks against Israel, we will return to the preventive-strike policy, including against leaders of the group,” Mofaz was quoted as saying in Yediot Achronot, using the official term for Israel’s targeted killings of top terrorists. “No one will be immune, even those in the political echelon.”

Yet in remarks to his Cabinet colleagues, Mofaz said Hamas was “acting responsibly” — a reference to the group’s efforts to quell international concerns by reaching out to rival Palestinian factions and toning down the more belligerent rhetoric against Israel.

Some Hamas leaders have proposed holding talks with Israel via mediators, or declaring a protracted cease-fire that would allow for direct contacts while keeping the “jihad option” alive in perpetuity.

Neither option is acceptable to the Olmert government, a stance that has been backed by both his Likud and Labor party challengers in the March 28 general elections.

Though less than a month in power, having succeeded Prime Minister Ariel Sharon after his Jan. 4 stroke, Olmert is the beneficiary of months of work invested by Foreign Minister and Justice Minister Tzipi Livni in enlisting foreign support for shunning Hamas from the political sphere.

The United States and European Union have already made clear they could stop donor aid to the Palestinian Authority unless Hamas radically changes its stripes.

“These principles are accepted by the international community. On this issue, I don’t intend to make any compromises,” Olmert said.

The acting prime minister’s first face-to-face endorsement was to come from German Chancellor Angela Merkel, who arrived in Israel on Sunday for her first official visit. Though Merkel was also to meet with Palestinian Authority President Mahmoud Abbas, she made clear her itinerary would not include Hamas officials.

Israel has an interest in seeing Abbas’ standing boosted. Despite the collapse of the Palestinian Authority government, he remains president. As Israel still considers him a potential interlocutor, he can present this as an asset set against the international isolation in store for Palestinians under a Hamas regime.

“Abbas has become a real reluctant hero,” the chief of the Shin Bet, Yuval Diskin, told the Cabinet.

Merkel’s support is doubly important because her country is one of three in the European Union that has tried — with little success — to convince Iran to abandon its nuclear weapons efforts. The German chancellor was expected, while in Israel, to formally seal a deal to sell the Jewish state two new Dolphin submarines, a move that would expand its fleet to five and improve its strategic capabilities.