Iran’s foreign minister denounced Israeli Prime Minister Benjamin Netanyahu’s allegations against Tehran at the UN General Assembly as an “obscene charge”, the state-run IRNA news agency reported on Friday.

The response came after Netanyahu on Thursday claimed at the General Assembly that Iran has a “secret atomic warehouse” on Tehran’s outskirts and challenged UN inspectors to examine it.

It was unclear whether Netanyahu’s announcement sheds new light on what UN inspectors already know, or whether it was intended to prove that Iran has been violating the landmark 2015 nuclear deal with world powers that followed years of Western sanctions over the country’s contested atomic program.

According to IRNA, Foreign Minister Mohammad Javad Zarif called Netanyahu a “liar who would not stop lying”.

The 2015 nuclear deal saw Iran drastically limit its enrichment of uranium — a possible pathway to atomic-grade weapons — in exchange for the lifting of crushing economic sanctions. Iran long has denied seeking nuclear weapons and claimed its program is for peaceful purposes only.

In May, President Donald Trump pulled America out of the nuclear deal, in part due to Tehran’s ballistic missile program, its “malign behavior” in the Mideast and its support of groups like Hezbollah. The Trump administration has also been re-imposing sanctions on Iran, plunging its economy further into a downward spiral.

For his part, Zarif tweeted that Israel’s the only one with an “undeclared” nuclear weapons program in the region and that it should open it to international inspectors.

“No arts & craft show will ever obfuscate that Israel is only regime in our region with a (asterisk)secret(asterisk) and (asterisk)undeclared(asterisk) nuclear weapons program - including an (asterisk)actual atomic arsenal(asterisk). Time for Israel to fess up and open its illegal nuclear weapons program to international inspectors,” Zarif said on his Twitter account.

The spokesman of the Iranian Foreign Ministry, Bahram Ghasemi, said Netanyahu’s accusation was “not worth talking about”.

“These farcical claims and the show by the prime minister of the occupying regime (Israel) were not unexpected,” Ghasemi added.

Iran’s deputy foreign minister, Abbas Araghchi, mocked Netanyahu, saying the Israeli leader must have been badly advised by some people.

Netanyahu is known for showmanship at the UN General Assembly. In 2012, he famously held up a cartoon of a bomb before the UN audience while discussing Iran’s nuclear program.

Netanyahu made a similarly splashy accusation in May, saying Israeli agents spirited away a “half ton” of documents regarding Iran’s nuclear program from a facility in Tehran’s Shourabad neighborhood.

Separately, Netanyahu in his speech before the General Assembly also held up an image of what he said are rocket factories run by the Iran-backed militant Hezbollah group, hidden in civilian areas of Beirut.

In response, Lebanese Foreign Minister Gebran Bassil tweeted that Israel was “fabricating pretexts” to launch an attack on Lebanon “from the podium of international legitimacy”.

The Israeli military had said Hezbollah is attempting to establish missile conversion infrastructure near Beirut’s Rafik Hariri International Airport.

Last week, Hezbollah’s leader Hassan Nasrallah boasted how the Shiite militant group now possesses “highly accurate” missiles despite Israeli attempts to prevent it from acquiring such weapons. He did not elaborate on the missiles.

A Hezbollah spokesman in Beirut said on Friday the group has “no comment” on Netanyahu’s claims.