Her calls follow the publication of a report criticising the decision to initiate last summer's Israeli-Hizbullah conflict, which was widely seen as a victory for the Lebanese paramilitary group.
"I told the prime minister that resignation is the right thing to do," Ms Livni said.
Whereas she escaped the report relatively unscathed, Mr Olmert, his already-departed chief of staff Dan Halutz and defence minister Amir Peretz all attract criticism.
Lieutenant General Halutz left his job in January and Mr Peretz is said to be considering his resignation, but the prime minister has maintained his position that the report's political impact should not be overplayed.
"To all those who are in haste in order to take advantage of the report for political profit, I tell them not to be hasty," he said at the start of the session.
The 34-day conflict saw the deaths of 160 Israelis and well over 1,000 Lebanese citizens. Military incursions into southern Lebanon were ordered by Mr Olmert after the kidnapping of two soldiers, who remain missing today.
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