Israeli Prime Minister Benjamin Netanyahu on Saturday dismissed seemingly conciliatory statements from Iran as a smokescreen to divert attention from Tehran's efforts to build nuclear arms.

In a statement from his office, Netanyahu brushed off remarks in which Iranian officials condemned the Holocaust and even wished Jews a happy new year.

He called on the international community to increase pressure on the Islamic republic.

"I am not impressed by greetings coming from the regime which just last week threatened to destroy Israel," said Netanyahu.

"The Iranian regime will be judged solely on its deeds, not its greetings, whose only purpose it to distract attention from the fact that even after the elections it continues to enrich uranium and build a plutonium reactor with the aim of acquiring a nuclear weapon which will threaten Israel and the whole world."

Iran's army chief of staff General Hassan Firouzabadi was quoted by the official IRNA news agency on August 29 as saying that a US-led military strike against Tehran's ally Syria would leave American protege Israel in flames.

In contrast, new Iranian President Hassan Rowhani is waging a public relations campaign to improve the Islamic republic's image, after years of bad press over Tehran's atomic ambitions and incendiary comments by former president Mahmoud Ahmadinejad.

In his first remarks since Rowhani tasked him with taking over Iran's sensitive nuclear talks with world powers, Foreign Minister Mohammad Javad Zarif said Tehran wants to calm fears over its atomic programme.

"Allaying international concerns is in our interest because atomic weapons do not form part of the Islamic republic's policies," Zarif said on Friday.

Iran says its nuclear ambitions are for entirely peaceful purposes, despite fears in Israel and among world powers that its uranium enrichment masks a covert weapons drive.

Zarif, a US-educated moderate and former ambassador to the United Nations, said on Facebook this week that Tehran condemns the World War II Nazi massacre of the Jews, in stark contract to Holocaust denials by Ahmadinejad.

In an interview published on his Facebook page, he confirmed reports he had tweeted best wishes for the Jewish new year in an exchange with Christine Pelosi, daughter of the Democratic leader in the US House of Representatives, Nancy Pelosi.