"Iran wants to be in a position to rush forward to build nuclear bombs before the international community can detect it and much less prevent it," Netanyahu said in an address to the 68th annual session of the UN General Assembly in New York on Tuesday.
"Israel will not allow Iran to get nuclear weapons. If Israel is forced to stand alone, Israel will stand alone," he claimed.
Netanyahu added that a "nuclear-armed" Iran would be a threat to Israel’s future and called on the international community to keep up pressure on Tehran through sanctions.
Netanyahu's salvo of threats and accusations against Iran comes as Tehran has categorically rejected allegations leveled by the US, Israel and some of their allies against its nuclear energy program, arguing that its nuclear energy program is only for peaceful purposes.
In a meeting with US President Barack Obama in Washington on Monday, Netanyahu claimed credible military threat and sanctions have brought Iran to the negotiating table.
He called on Obama to tighten economic sanctions on Iran if it continues its nuclear advances during a coming round of talks with the West, saying, "Those pressures must be kept in place."
Israel is widely believed to be the only possessor of nuclear weapons in the Middle East, with estimated 200-400 nuclear warheads.
The Israeli regime rejects all regulatory international nuclear agreements, particularly the Non-Proliferation Treaty (NPT), and refuses to allow its nuclear facilities to come under international regulatory inspections.