Iran’s Supreme Leader Ayatollah Ali Khamenei put a wrinkle in his country’s “charm offensive” on Sunday, saying Israel was an “illegitimate and bastard regime.”

His comments, posted on his Twitter account, came just a few days before a second round of talks in Geneva between his nuclear negotiators and the P5+1, made up of the US, Russia, China, Germany, France and Britain.

Even before Khamenei’s tweet, Prime Minister Binyamin Netanyahu, speaking at the opening of the weekly cabinet meeting, said, Iran was “openly and directly” calling for Israel’s destruction.

“Iran is continuing to try and arm itself with nuclear weapons; it has not changed its goal – the method maybe, but not the goal – and it has not changed its ideology,” he said.

Netanyahu pointed out that Monday is the 34th anniversary of the seizure of the US Embassy in Tehran, a day celebrated in Iran as “Death to America Day.”

“This makes it clear that pressure on the Iranian regime must be continued,” Netanyahu said. “The pressure has brought them to the negotiating table. I am convinced that if the pressure is maintained and not relaxed, Iran will dismantle its military nuclear capabilities, and if the pressure is relaxed, Iran will advance toward this goal. We are committed to ensuring that it does not reach its realization.”

Outgoing National Security Council head Yaakov Amidror, speaking at a going-away reception on his last day in office, said Iran is Israel’s one “clear existential threat.”

He said Israel must do everything it can to remove that threat, “if possible, through negotiations, and if not possible through negotiations, then by other means.”

Amidror’s position will now be filled by Mossad veteran Yossi Cohen.

Netanyahu was not the only one highlighting that Monday marks the anniversary of the takeover of the US embassy in Tehran; Khamenei also underlined this in a number of tweets posted on his account.

Iran’s supreme leader tweeted that he was meeting with leaders of students who 30 years ago called the US Embassy a “den of spies.”

Furthermore, referring to the scandal engulfing the US National Security Agency for spying on both allies and rivals, Khamenei said that today, US embassies in countries that are its closest allies were being called spy dens, meaning that “our young revolutionaries are 30 years ahead.”

Just five days before negotiations begin with the West, those running Khamenei’s account tweeted messages reflecting the intense internal debate in Iran regarding the meetings. He sent out a dual and somewhat contradictory message of not trusting the US negotiators on the one hand, but at the same time not criticizing those negotiating with the US and labeling them “compromisers.”

“No one should consider our negotiators as compromisers, they are our own children and the children of the revolution,” his Twitter account read.

“Our negotiators are in charge of a difficult task and no one should weaken an agent who is engaged doing work.”

Khamenei tweeted that he was not optimistic about the outcome of the negotiations, and that even if they failed, it would increase Iran’s selfreliance.

He advised against “trusting an enemy who smiles” and “expresses a desire for talks,” while on the other hand says “all options are on the table.”

One Israeli official, referring to Khamenei’s comments about Israel being a “bastard regime,” said his words “reveals the true mindset of the regime.”

“This should be a wake-up call for people who have the illusion that the Iranians have become more moderate,” he said. “This represents the policy goals of the regime, and it means Israel was born illegitimately and therefore should not be here.”