JERUSALEM (CNN) -- Benjamin Netanyahu, the head of the conservative Likud Party, has been chosen to form Israel's next government, Israeli President Shimon Peres announced Friday.

Netanyahu (left) shakes hands with Peres, who has asked him to form the next Israeli government. more photos »

At a joint news conference with Peres, Netanyahu said he accepted the task and he is willing to work with the moderate parties of Labor, led by Ehud Barak, and Kadima, headed by Foreign Minister Tzipi Livni.

"We have different approaches in different areas, but we are all together in our desire to act for the good of the state," Netanyahu said. "We will be able to find the common ground to lead the state toward security, prosperity and peace."

He said Israeli leaders need to unite as the country faces "great challenges," particularly from Iran, which he said "is developing nuclear weapons and poses the biggest threat to Israel since the war of independence."

A U.N. report released this week found that Iran has enough uranium for a single nuclear weapon, but the uranium has not been enriched to make it weapons-grade. Iran consistently has denied the weapons allegations, calling them "baseless," and said that data that indicated otherwise was "fabricated."

To become Israel's next prime minister, Netanyahu must form a coalition within six weeks, or the process will start all over.

The decision comes after Avigdor Lieberman, head of the right-wing Yisrael Beytenu party, said he would recommend Netanyahu for the post, but only if he promises to form a "broad-based" coalition government.

In last week's parliamentary elections, no single party won the minimum 61 seats needed to form a government. That means a government of two or more parties -- or coalition government -- is inevitable. Watch election analysis from CNN's Bill Schneider »

The ruling Kadima Party won the most seats in the Knesset, Israel's parliament. But Kadima received just one more seat than Netanyahu's Likud Party.

The strong showing of other right-wing parties -- including Yisrael Beytenu and the Orthodox Shas movement -- could give Netanyahu a better chance of forming a coalition government.

Speaking to fellow Likud members Monday, Netanyahu expressed confidence that he has enough support to emerge as Israel's next prime minister.

"I plan to form a government as soon as possible with our natural partners," the former Israeli prime minister said. "We have a government in our hands, but we want a broader one."

He added that he will negotiate with other parties, including Kadima, "to form a broad national unity government."

Livni took over as Kadima leader after Prime Minister Ehud Olmert stepped down from the post amid corruption investigations. Livni's failure to assemble a ruling coalition at that time triggered last week's elections.

Netanyahu, 59, is a former Israeli soldier who served in the elite commando unit Sayeret Matkal. He was one of a dozen Israeli commandos who stormed a Belgian aircraft hijacked by Palestinian terrorists in 1972 and helped rescue 140 hostages.

After his stint as prime minister from 1996 to 1999, he served in the Cabinet of Prime Minister Ariel Sharon, then Likud Party leader, but resigned in 2005, saying he disagreed with Sharon's plan to remove Israeli troops and settlements from Gaza. Sharon left Likud and formed Kadima as a more centrist party.

Netanyahu has supported the expansion of Israeli settlements on the West Bank and has opposed making further territorial concessions in hope of ending the decades-old Israeli-Palestinian conflict.

He has been reminding the public that he warned that Palestinian militants in Gaza could launch rockets at Israeli cities such as Ashkelon and Ashdod -- which has happened and led to Israel's recent military operation in Gaza.

His Likud Party had a strong showing in last week's election, more than doubling the number of seats it holds in the Knesset. Netanhayu said that showing proves that voters have rejected Kadima's leadership, and he predicted right-leaning parties will be able to form a majority.

"With God's help, I shall head the coming government," he said. "I am sure that I can manage to put together a good, broad-based and stable government that will be able to deal with the security crisis and the economic crisis."

CNN's Michal Zippori contributed to this report.

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