Tens of thousands of Israelis have gathered at a Tel Aviv square calling for Benjamin Netanyahu to be replaced as the prime minister in national elections scheduled to be held on March 17.
Police gave no official figures, but Israeli media said that about 30,000 people attended the rally on Saturday, which was held under the banner "Israel wants a change."
The rally's keynote speaker was Meir Dagan, a former Mossad chief, who recently criticised Netanyahu's conduct and called him "the person who has caused the greatest strategic damage to Israel".
"Bibi, you've failed, go home," the demonstrators chanted, referring to Netanyahu by his nickname.
Opinion polls show Netanyahu's right-wing Likud running neck-and-neck with rival Isaac Herzog, head of the centre-left Zionist Union, linked to the Labour party.
Netanyahu, seeking a fourth term in office, is seen as having a slight advantage of more parliamentary allies with whom to form a coalition government.
Latest polls have both Zionist Union and Likud winning 23 of the Knesset's seats.
Netanyahu has focused his campaign on security issues and the Iranian nuclear programme, and the demonstration organisers appeared to be challenging him on his home turf by featuring Dagan as the headline speaker.
"For six years, Mr Benjamin Netanyahu has been serving as prime minister. Now it has been six years in which Israel has never been more stuck," Dagan said, accusing Netanyahu of failing in dealing with Iran and forfeiting Israel's interests for the sake of his own political survival by not pushing for a peace deal with the Palestinians.
"In six years he has not lead one real move to change the region and to create a better future."
US-led international talks are under way to persuade Iran to restrain its nuclear programme in exchange for relief from sanctions that have crippled its economy.
Netanyahu drew strong criticism from the administration of Barack Obama and in Israel for a speech he gave at the US Congress on Tuesday where he criticised the emerging deal.
His opponents said he had damaged Israel's strategic alliance with the US.