Former Israeli foreign minister Tzipi Livni is returning to politics forming a new party to run in January's parliamentary elections.
Ms Livni said the party, called "The Movement," would aggressively pursue peace with the Palestinians.
She criticised prime minister Benjamin Netanyahu's hard-line government for the past four years of deadlock in peace efforts.
She said she "decided to give an answer to people who don't have anyone to vote for."
Ms Livni's return adds another name to what already is a fractured centrist opposition.
She served as foreign minister and chief peace negotiator from 2006 to 2009. She left politics this year after she was ousted as leader of the Kadima Party.