A top Israeli security official warned on Wednesday that a Palestinian campaign to seek UN recognition of a state was likely to stoke new tension with Israel, the Jerusalem Post reported.
The paper's website quoted Yuval Diskin, head of the Shin Bet domestic security agency, as telling a parliamentary committee that September "will be a boiling point."
The Palestinians have said they intend to unilaterally declare statehood in September, when the United Nations opens its annual General Assembly.
He said it was not certain that the Palestinian leadership would carry out its stated aim of taking its case to the UN Security Council and possibly to the General Assembly, but cautioned that Israel must be prepared.
"Israel needs to create a situation in which there is a border, border crossings and border police between us and the Palestinians, even if it is a temporary and unrecognised border," the Post quoted him as saying.
"If we do not take care to do so, we will find ourselves in a situation that will not allow us to make that separation."
Since the collapse of direct negotiations with Israel in September, following the expiry of a moratorium on Israeli settlement building in the West Bank, the Palestinians have pursued a diplomatic campaign to win world recognition.
Chief Palestinian negotiator Saeb Erakat said on Wednesday that a UN resolution condemning Israeli settlement building would be put to the vote next month, with support from Russia and France.
Such a move is seen as a rehearsal for a possible bid for full UN membership later in the year.
"This process is gaining momentum because the Palestinians have recognised gaps between Israel and the United States, and export their struggle to the international community," Diskin told the lawmakers.