An Israeli-Arab politician who took part in an attempt to breach the blockade of Gaza has been disqualified from standing in next month's general election after being accused of undermining the state of Israel.

The central elections committee voted 19-9 to back a motion brought by rightwingers against Haneen Zoabi's candidacy. The decision has been automatically referred to the supreme court, which must rule before the end of the month.

Before the hearing, Zoabi said her disqualification would mean "disqualifying an entire generation of young Arabs".

Danny Danon, a member of parliament for the ruling Likud party who presented a 11,000-signature petition calling for Zoabi's disqualification, told the Guardian: "Her place is not in the Knesset [Israeli parliament] but in jail. Democracy must have its limits." Zoabi had worked "against the interests of the state and for our enemies," he added.

One of 11 MPs representing Arab parties, Zoabi has faced a robust campaign since she took part in a flotilla of ships attempting to breach Israel's blockade of Gaza in May 2010. Nine Turkish activists were killed when Israeli commandos stormed the lead ship, the Mavi Marmara, on which Zoabi was a passenger.

Her parliamentary privileges were revoked but an attempt to bring criminal charges against her failed. She was assigned special protection after a number of death threats were made against her.

The committee cited Zoabi's participation in the flotilla as the chief reason for her disqualification.

David Rotem, an MP for the far-right Yisrael Beiteinu party, told the committee: "To say that a member of Knesset was aboard the Mavi Marmara does not constitute the critical mass equalling support for a terrorist organisation reflects a lack of understanding of what happened aboard that ship."

Another far-right MP, Michael Ben-Ari, said the aim of the disqualification was to ensure "our kids will be able to live in a normal Jewish state, not one in which 30 Zoabis serve in the Knesset".

Jamal Zahalka, the leader of Zoabi's Balad party, earlier said his party would boycott the election in the event of her disqualification.

"Our problem is not that we are terrorists but rather that we are democrats in an environment that does not believe in democracy," he said. "We are tired of apologising for demanding full equality for all Israeli citizens. We're tired of sitting in the dock for being patriotic Palestinians."

Israel's attorney general had advised that there were insufficient grounds to disqualify Zoabi.

The committee voted against disqualifying Balad and another party representing Arab citizens of Israel, Ra'am-Ta'al, from fielding candidates. It has yet to consider petitions to bar three religious Jewish parties.