As Israeli Prime Minister Benjamin Netanyahu prepares to take office for a third time, his attempts to form a new coalition government have gotten off to a rocky start.

Netanyahu is vowing to form a broad-based government to tackle the country's challenges in the coming years, but that won't be easy. Given the dizzying array of potential coalition partners and their deep differences on key issues, Netanyahu will be hard pressed to build a stable government, much less make significant progress on such divisive matters as drafting ultra-Orthodox Jewish seminary students into the military and pursuing peace with the Palestinians.

"There are very serious disputes that will be very hard to resolve," Reuven Rivlin, a senior member of Netanyahu's Likud Party, told Israel Radio on Tuesday.

Netanyahu got the nod to form a new government Saturday night, following a Jan. 22 election. He has six weeks to put a team together. The gloves typically come off early in the negotiations but eventually end up with a coalition.

The sniping has already begun.

Newcomer Yair Lapid, whose party came out of nowhere to become the second largest in the parliament, is thought to be an important partner for Netanyahu.

But Lapid was quoted this week by Israeli media as saying that he is ready to become the parliamentary opposition leader and could force new elections that would make him the prime minister within 18 months. Netanyahu's allies have seized on the reported comments to depict Lapid as arrogant and intransigent.

Netanyahu's close ally, Avigdor Lieberman, said Tuesday that he was shocked to hear that a political rookie already has his eyes set on the prime minister's job. "That is a new phenomenon," he told Israel Radio. "I only hope that this is temporary, and we can return to negotiations about real issues."

Rivlin, a veteran of decades of backstage political maneuvering, explained why the sometimes ugly negotiations have to work out in the end with the formation of a government — because failure means another election. That has never happened in Israel.

"Never before has Israel needed to have such a wide government, because every problem or dispute could spark the need for new elections," he said. "I don't think any of the 120 members, especially the 50 newly elected ones, would want to go to elections again in a few months."

Netanyahu's Likud-Yisrael Beitenu bloc won the most seats in last month's parliamentary election. But with just 31 seats, Netanyahu needs to bring in multiple coalition partners to secure a majority of at least 61.

He can pursue two main choices — either form a narrow coalition with the hard-line and religious parties that have traditionally backed him, or try to build a broader, more moderate coalition.

Each choice has risks.

Netanyahu's traditional allies hold a total of 61 seats, so this option is mathematically possible. But a narrow coalition would be unpopular with the public following an election in which secular, centrist candidates did surprisingly well.

With the government required to pass a budget in the coming months after posting a larger-than-expected deficit last year, a narrow coalition would leave Netanyahu vulnerable to political extortion by partners threatening to bring down his government.

For now, Netanyahu is pledging to court more centrist partners, believing a larger coalition will be more stable and better capable of addressing the nation's needs.

"It is inconceivable that the most challenging country in the world should suffer from instability and weak governance," Netanyahu told a welcoming ceremony for the new parliament on Tuesday. "We need stability to deal with the quality of living for the citizens of Israel, but also to guarantee something far more superior and important."

In his comments, Netanyahu laid out an ambitious agenda: He vowed to reform the country's compulsory military draft "in a way that will not tear this nation apart" and to find ways to reduce Israel's high cost of living.

He said Israel must face "new and mounting threats," a reference to Iran's suspect nuclear program and the turmoil sweeping the region. Netanyahu also pledged to pursue a "secure, stable and realistic peace" with the Palestinians.

Despite Netanyahu's appeals for unity, any one of these issues could rip apart a future coalition. Ending the country's contentious system of giving out draft exemptions to Jewish seminary students would alienate potential ultra-Orthodox partners. Failing to do so would drive away centrists like Lapid, who made the issue a centerpiece of his campaign.

Negotiations with the Palestinians are just as contentious.

Peace talks remained frozen during Netanyahu's just-completed four-year term, and he is under heavy international pressure to get negotiations back on track. When President Barack Obama visits in the spring, he can be expected to increase the pressure on Israel to come forward with an initiative.

Restarting peace talks with the Palestinians will likely require new concessions by Netanyahu that would be opposed by his hard-line base of support. Netanyahu's own party is dominated by lawmakers who reject concessions to the Palestinians. A likely partner, the pro-settler Jewish Home, even advocates annexation of large parts of the West Bank, the heartland of any future Palestinian state.

Yet Lapid, among others, has said he will not participate in a government that is not conducting serious peace negotiations.