Tzipi Livni, the former Israeli foreign minister who led her party to an ill-fated election victory in 2009, has announced she is retiring from politics.
The veteran politician said her Hatnuah party would not run in the April 9 election in order to prevent the disparate centre-left bloc from losing votes.
It comes after her Zionist Union alliance with the Labour Party was dramatically disbanded by its leader Avi Gabbay during a joint press conference that was televised live.
Both parties in the alliance have since plummeted in Israeli opinion polls, with Ms Livni's Hatnuah appearing at risk of not receving the minimum number of votes needed to win seats in the Knesset.
"I am leaving politics but I will not allow the hope for peace to leave Israel," she said in a press conference on Monday, Haaretz reported.
"I have the internal strength to continue fighting but we don't have enough political power to actualise our vision on our own.
"I won't forgive myself if the votes of the believers [in my path] will go to waste."
Ms Livni had attempted to form an alliance with other parties in order to secure Knesset representation, but Monday's press conference indicates these efforts were unsuccessful.
In 2009, then leading the centrist Kadima, she led her party to the largest number of votes and seats in that year's election.
But right-wing parties secured more representation in the Knesset, leading then-President Shimon Peres to ask Benjamin Netanyahu, whose Likud party came second, to form the government.
Ms Livni began her career in 1999 as a member of Likud, but moved to the political left in the belief that Israel needed to confront what many consider to be a demographic time bomb caused by Israel's occupation of millions of Palestinians.
She followed then-Prime Minister Ariel Sharon into forming the breakaway Kadima faction in 2005 and served as foreign minister and chief peace negotiator with the Palestinians.