"I said that the attempts of the Palestinians and of several European countries to force conditions on Israel will only lead to a deterioration in the regional situation and will endanger Israel," he said in a statement.
"Therefore, we will strongly oppose this."
The comments followed almost three hours of talks in Rome between Netanyahu and US Secretary of State John Kerry, who jetted across Europe on Monday for a hectic round of meetings.
A State Department official said Kerry and Netanyahu "had a long and thorough discussion about Israel's security and developments at the United Nations".
On his third stop of the day, Kerry arrived late Monday in London having paused en route from Rome for less than two hours in Paris to meet with European counterparts.
The Palestinians have said they will submit an Arab-backed draft text to the UN setting a two-year deadline for Israeli troops to withdraw from Palestinian land as early as Wednesday.
France is putting together a more nuanced version setting a two-year timetable for concluding a peace treaty, without mentioning the withdrawal of Israeli forces.
Kerry met at Orly airport in Paris for late-night dinner talks with the foreign ministers of France, Britain and Germany inside the airport seeking clarification on the French-led resolution bid.
Traditionally the US has used its power of veto at the UN Security Council to shoot down what it sees as moves against its close regional ally, Israel.
US officials told reporters accompanying Kerry that Washington has not yet decided whether to veto or back the French-led UN initiative.
"There are certain things we would never support," said a State Department official, without elaborating.
French Foreign Minister Laurent Fabius told AFP they were looking for "a resolution which everyone can get behind".
"Even if the Palestinians have a text in their hand, the Americans have already said that they will veto it."
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Netanyahu earlier said: "We will not accept attempts to dictate to us unilateral moves on a limited timetable."
Jordan, which the Palestinians said would submit their resolution, maintained it had no immediate plans to push for an early UN vote.
Jordanian Ambassador Dina Kawar to the UN said: "Secretary Kerry is having meetings in Europe with a number of ministers so we are waiting to see what happens."
There is a growing impatience in Europe over the failure to make progress in peace talks, amid fears the Middle East risks spiralling into even greater chaos.
Several European parliaments have called on their governments to move ahead with the recognition of a Palestinian state.
The US administration opposes moves to bind negotiators' hands through a UN resolution -- particularly any attempt to set a deadline for the withdrawal of Israeli troops from the West Bank.
But a US veto risks running contrary to Washington's avowed aim of a Palestinian state and would anger key Arab allies -- many of whom are much-needed partners in the US-led coalition against Islamic State militants.
"We will stand firm in the face of any diktat," the Israeli leader said ahead of Monday's talks.
Kerry will meet Tuesday in London with chief Palestinian negotiator Saeb Erakat and the secretary general of the Arab League, Nabil al-Arabi.
France's Fabius is also to meet with Arabi on Tuesday.
Diplomatic sources say Paris is hoping to persuade the Palestinians to back their compromise resolution, rather than risk a US veto of the more muscular Arab version.
But the Palestinians appear divided amid frustration at the snail's pace of diplomatic efforts, with the final decision resting with Palestinian president Mahmud Abbas.