UNITED NATIONS - Israeli Prime Minister Benjamin Netanyahu on Thursday said that Iran has hidden "massive amounts of equipment and materiel," indicating that the country is eyeing nuclear weapon program.

Speaking at the General Debate of the UN General Assembly, Netanyahu said that nearly 15 kilograms of radioactive material had been stored in the warehouse in the Turquzabad district of Tehran.

"Today I am disclosing for the first time that Iran has another secret facility in Tehran, a secret atomic warehouse for storing massive amounts of equipment and materiel from Iran's secret nuclear program," Netanyahu said.

This site contained as much as 300 tonnes of nuclear-related equipment and materiel, he said, noting Iran hasn't abandoned its goal to develop nuclear weapons.

While not detailing what the material was, Netanyahu urged the International Atomic Energy Agency, a UN atomic watchdog, to inspect the location immediately.

Netanyahu also criticized Europe for setting up a legal entity to bypass US re-imposed sanctions, saying such action amounts to an appeasement with Iran.

On Monday, European Union foreign and security policy chief Federica Mogherini said that the EU will set up a legal entity to facilitate legitimate financial transactions with Iran in light of the US withdrawal from the international agreement on Tehran's nuclear program and the re-imposition of sanctions.

On Wednesday, leaders of France and Britain, while speaking at the UN Security Council (UNSC) meeting on non-proliferation, vowed to defend the Iran nuke deal.

All these showed that Washington, by exiting the deal and sanctioning Iran, has put itself in isolation, Iranian President Hassan Rouhani said.

Netanyahu on April 30 revealed what he called a "great intelligence achievement" about Iran's nuclear program, saying that he had proof that Iran had been seeking nuclear power even after it signed an agreement curbing its nuclear program in 2015.

However, Iranian Foreign Ministry later denounced his nuclear allegations against Iran as a "worthless show" and "ridiculous propagandist presentations" that were "merely aimed at spreading lies and deception."

Tensions between Iran and Israel, as well as the United States, have been running high this year.

US President Donald Trump said on Wednesday that the United States will impose "tougher than ever" sanctions on Iran after the punitive actions against the country slated in November this year.

In May, Trump announced Washington's withdrawal from the landmark Iranian nuclear deal. Since then, the Trump administration has slapped a number of sanctions on Iran while vowing to apply more in November.