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Former Foreign Minister Tzipi Livni announced her resignation from parliament on Tuesday, weeks after she was ousted as opposition leader, in a move that could shake up Israeli politics ahead of widely expected national elections.

Livni, a one-time chief peace negotiator who is widely respected internationally, vowed to remain active in politics. She has been rumored to be considering joining a new centrist party being formed by popular former TV anchorman Yair Lapid.

"I leave at this stage, but I'm not leaving public life," Livni said. "The citizens of Israel deserve more than the current policy."

Just a few years ago, Livni was one of the country's most popular politicians. A founder of the centrist Kadima Party, she served as foreign minister from 2006 to 2009, a time when she was Israel's chief negotiator with the Palestinians. That experience gained her respect in international circles and helped land her on lists of the world's most influential women compiled by such publications as Time, Forbes and Newsweek.

But in her three years as opposition leader, she faced heavy criticism for what was widely seen as an ineffective term. Kadima, which won 28 seats in 2009 elections, making it the largest party in parliament, has plummeted in opinion polls and is only expected to win about a dozen seats, if that, in the next vote.

Last month, Shaul Mofaz, a former Israeli military chief, trounced Livni in internal elections for Kadima's leadership, setting the stage for her departure.

By leaving the door open to continued involvement in political life, Livni's comments were likely to fuel more speculation that she would be joining Lapid's new "Yesh Atid" or "There is a Future" party. She did not elaborate on her specific plans.

Speaking to reporters at the Knesset, or parliament, Livni said the people of Israel "deserve more" than what the current leadership has given. With peace talks deadlocked for the past three years, she accused the government of ignoring the Palestinians.

Israel is sitting on a "volcano" and its survival as a Jewish, democratic state is in "mortal danger" if it does not find an accommodation with the Palestinians, she said.

"The real danger is a politics that buries its head in the sand," she said.

The Palestinians, and Israeli doves, have warned that Israel risks turning into a "binational" state of Jews and Arabs if a Palestinian state is not established in the West Bank, east Jerusalem and Gaza Strip.

Some 4 million Palestinians live in these areas, and combined with Israel's own Arab population, they could soon outnumber the roughly 6 million Jews living in Israel.

Israeli Prime Minister Benjamin Netanyahu signaled this week that he would soon call early elections. The next vote is scheduled in October 2013, but an array of issues, including disagreements in Netanyahu's coalition over draft exemptions for ultra-religious Jews, threaten to tear the government apart.

Netanyahu, who is mourning the death of his father, was expected to make a decision next week.

An opinion poll this week predicted Netanyahu's Likud would remain the largest party in parliament if elections were held now, with 30 seats in the 120-member chamber.

But the poll said an alliance joining Livni and Lapid would be the second-largest party, with 16 seats. Combined with the resurgent Labor Party and the remnants of Kadima, this dovish bloc could pose a formidable challenge to Netanyahu if he tries to cobble together another hard-line coalition.

The poll of 500 people was published Monday by the Dahaf institute, a prominent polling agency. It had a four-seat margin of error and reflected other recent surveys.