Israeli President Moshe Katsav has warned that the opposition of pro-settler rabbis to Israel's Gaza pullout could incite ultranationalists to try to assassinate Prime Minister Ariel Sharon.
"In the struggle over the disengagement someone is likely to distort the rabbis' messages," Mr Katsav told Army Radio.
The result, he said, could be "extremist actions" and "the distorted conclusion that to prevent Israel's destruction, one must assassinate the prime minister".
Mr Katsav made the comments a day after the Shin Bet security service measured Mr Sharon and members of his cabinet for bulletproof vests, a sign of mounting fears of violence against Israeli leaders ahead of the pullout due to begin in mid-August.
In recent weeks, some pro-settler rabbis have sharpened their rhetoric against the withdrawal from land they see as a biblical birthright, condemning it as a violation of Jewish law and a danger to Israel's existence.
Such talk has revived memories of the verbal attacks against Prime Minister Yitzhak Rabin before he was assassinated in 1995 by an ultranationalist Jew opposed to his peace moves with the Palestinians.
Jewish settler leaders have called for passive resistance to the evacuation of all 21 Jewish settlements in Gaza and four of 120 in the West Bank.
Hoping to sharpen that message, right-wing legislator Effi Eitam said he planned to meet rabbis and settlers to draw up a charter of non-violence to avoid clashes with Israeli soldiers during the pullout.
Israeli security officials have said they plan to collect the army-issued weapons that many of the 8,500 settlers facing evacuation carry.
Last week, ultranationalists threw rocks at Israeli soldiers who evicted them from an abandoned house they seized in a Palestinian neighbourhood adjoining a Jewish settlement bloc in the Gaza Strip.