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Benjamin Netanyahu won the endorsement Thursday of an anti-Arab politician who emerged from Israel's election as a kingmaker, virtually ensuring that the hawkish, U.S.-educated politician will once again become prime minister.

The big question is whether Netanyahu will be able to build the broad coalition he will likely need to stay in power and avoid clashing with the Obama administration and much of the world.

With his top rival, centrist Foreign Minister Tzipi Livni, signaling that she would enter the opposition, Netanyahu's prospects for such a coalition do not look good. He will probably have little choice but to forge a coalition with nationalist and religious parties opposed to peacemaking with the Palestinians and Israel's other Arab neighbors.

One major Orthodox Jewish party, Shas, also threw its support to Netanyahu, joining a group of similar movements that did the same.

"Today the foundations were laid for an extremist right-wing government under the leadership of Netanyahu," Livni said in a text message to 80,000 members of her Kadima Party. "That is not our way and there is nothing for us in such a government... We must be an alternative of hope and go into opposition."

If Livni stays out of Netanyahu's government, it would almost surely hurt Netanyahu's credibility with the United States and Europe. And his hold on power would be more tenuous in a narrow coalition of rightists, with hard-line allies threatening to bring down his government in the face of any concession for peace.

Livni seeks a negotiated settlement with the Palestinians, a position supported by the Obama administration, while Netanyahu's partner on the right, Avigdor Lieberman, has drawn opprobrium with his call for Israel's 1 million Arabs to swear allegiance to the Jewish state or lose their citizenship.

Israel's ceremonial president, Shimon Peres, held talks with political parties before choosing a candidate to form a government. Peres is scheduled to meet separately Friday with Netanyahu and Livni, and is likely to make his choice over the weekend, the daily newspaper Haaretz reported. If he names Netanyahu, as seems likely, then Netanyahu will have six weeks to create a coalition.

Israeli Army Radio reported Thursday night that if tasked by Peres, Netanyahu would immediately invite Livni and Labor leader Ehud Barak to join him in government.

"In light of the great challenges which Israel faces — Iran, terrorism, the economic crisis and job losses — a national unity government is the order of the hour," the station's Web site quoted him as saying.

Netanyahu aides could not be reached for comment.

Barak, himself a former premier, has already said he will take the center-left Labor Party into opposition.

Livni has said she will not join Netanyahu unless she can be an equal partner, presumably through the sort of "rotation" agreement Israel has tried in the past in which an election's top two winners each get to be prime minister for two years.

One reason that a rightist government could be unstable is that Lieberman's secular agenda puts him squarely at odds with religious parties, such as Shas, clouding prospects.

Also Thursday, Sen. John Kerry, D-Mass., traveled to the Gaza Strip, the highest-level visit by a U.S. official since the Hamas militant group seized power in the territory nearly two years ago. He did not meet with anyone from Hamas, which the U.S. shuns as a terrorist group, and used the visit to urge the group to end its violence against Israel.

Lieberman's Yisrael Beiteinu (Israel is Our Home) Party finished third in the Feb. 10 election, after Kadima and Netanyahu's Likud Party. That essentially allowed him to determine whether Netanyahu or Livni would be able to muster the backing of a majority in the 120-seat Knesset, or parliament.

Lieberman's stance toward Arabs has exposed him to charges of racism, and many see him as a far-right extremist. However, he is opposed to the Orthodox Jewish establishment's control over key aspects of public life in Israel, one of several positions that has enabled him to find common ground with moderates.

While announcing support for Netanyahu, Lieberman said he preferred a national unity government that included Livni over a narrow coalition of right wingers.

"We need a wide government with the three big parties, Likud, Kadima and Yisrael Beiteinu," Lieberman said. "Netanyahu will lead the government but it will be a government of Netanyahu and Livni together."

Putting together a broad, centrist government would be a tall order for Netanyahu.

Livni has said she will not join Netanyahu unless she can be an equal partner, presumably through the sort of "rotation" agreement Israel has tried in the past in which an election's top two winners each get to be prime minister for two years.

Both Netanyahu and Lieberman — buoyed by the clear majority for the hawkish parties — have ruled out a rotation.

It's also unlikely the hard-liners would agree to Livni's key demand for pressing ahead with peace talks with the Palestinians and Syria.

All this will pressure Netanyahu to rely on the sort of narrow coalition whose members could dictate or torpedo policy and force him from office on a whim — especially if he adopts any conciliatory policies toward the Palestinians that his ultranationalist partners oppose.

"If Netanyahu wants cohesion and peace among the ranks of his coalition, that would mean isolation from the rest of the world," said political scientist Menachem Hofnung. "If he wants to avoid international condemnation and isolation, then he will face cracks and dissent from within his coalition."

Hofnung said he believes Netanyahu will ultimately give in to Livni's demands for joining the government.

In Washington, former U.S. Ambassador Martin Indyk said Netanyahu would pursue "economic peace" with the Palestinians, removing roadblocks to the flow of people and goods, but wants to avoid territorial concessions on the West Bank.

Netanyahu will attempt to deflect pressure from Obama and adviser George J. Mitchell by trying to make peace with Syria instead, offering to relinquish the Golan Heights, strategic land captured in the 1967 Mideast war, provided Israel was secure on that front, Indyk said at the Brookings Institution.

Netanyahu showed a pragmatic side as prime minister from 1996-99, meeting with Palestinian leader Yasser Arafat and ceding part of the biblically significant West Bank city of Hebron to Palestinian control.

However, the Likud leader says he will allow existing Jewish settlements in the West Bank to expand. He recently told a security conference that any territory Israel relinquished to the Palestinians in a peace deal would be "grabbed by extremists."

He says peace efforts should focus on building the Palestinian economy rather than creating an independent state — a nonstarter for the Palestinians and one of several stances that could put him at odds with Obama.

In forming a coalition, Netanyahu has said he would turn to religious and nationalist parties. But he has also expressed support for a government that reflects a broad national consensus.

Kadima edged out Likud in the election, capturing 28 seats to Likud's 27. But Likud is in a better position to make a coalition because of gains by Lieberman and other hard-line parties.