Rabbi Meir Kahane's Kach party, which campaigns to expel the two million Arabs under Israeli rule, was banned on Wednesday from running in the November 1 national election.
The Central Election Committee ruled against the New York-born Kahane, who entered parliament in 1984, citing a new law barring racist and anti-democratic parties from seeking public office."This was a real lynch," the 56-year-old Kahane told Reuters after the ruling.
Gad Servetman, Kach's public relations adviser, added: "Our campaign is running as if nothing has happened. Our next step is to appeal to the Supreme Court."
The Israeli High Court allowed Kahane to run for office in 1984, overturning an election committee decision, because there was no law ruling him out. Parliament passed a law in 1985, hoping to bar Kahane in the next election.
Most opinion polls show that Kahane, Kach's only member in the 120-seat parliament, could win four seats in November.
Kahane, however, cites other surveys giving him 12 seats to make Kach the largest party after Labor and the Likud, Israel's two main parties.
His followers, many of them young, first-time voters waving yellow flags emblazoned with Kach's clenched-fist symbol, have been drawn by his answer to a 10-month-old Palestinian uprising against Israeli rule in occupied territories.
Although shunned by other politicians and banned by the news media, Kahane has addressed numerous rallies, telling followers the Israeli people will one day elect him prime minister on a promise to expel the Arabs.