A former American diplomat says Israeli elements within the United States government are behind the continued harassment of US citizens who are among the guests of the annual Iranian-based New Horizon Conference (NHC).

Ever since February, when the NHC was sanctioned by the US Treasury over claims that it was a cover for Iranian intelligence agencies, the US Federal Bureau of Investigation (FBI) has been harassing the American scholars and experts who had either attended the event in past years or planned to attend the next one in Beirut, Lebanon’s capital, in September.

Among the individuals approached by the FBI are Michael Maloof, a former Pentagon official; William Springmann, a former US diplomat in Saudi Arabia; Scott Rickard, a former translator with the US Air Force and National Security Agency (NSA).

What connects the three pundits is their naked criticism of Israel and its policies as well as the “special relationship” the regime enjoys with Washington through various outlets, including Press TV.

The FBI has also raided the home of prominent African American author and scholar, Professor Vernellia Randall, who wrote the book "Dying while Black."

Springmann confirmed to Press TV in an interview on Sunday that the FBI had indeed called him earlier this year and asked him to answer their questions about the New Horizon conference he attended in Mashhad last year, but he turned them down.

The former diplomat said the US Treasury’s sanctions against the conference meant that any American individual partaking in the event could looking at a wide range of punishments from fines of $50,000 for a civil rights violation all the way to years-long prison sentences.

The analyst said Rickard had told him in person that the FBI threatened him with prison if he ever attended any event organized by the New Horizon organization.

“So they are really trying hard to prevent Americans from learning about Iran, experiencing Iran, exchanging ideas with anyone from Iran,” he said, blaming the trend on Israel’s policies.

He said at the heart of the decision-making process was Sigal P. Mandelker (pictured below), the Under Secretary of the Treasury for Terrorism and Financial Intelligence.

Springmann said Mandelker was an Israeli citizen who moved to America and “somehow” managed to take over important posts in the US administration.

“She seems to be doing the bidding of Israel by targeting Muslim and Arab organizations and anyone who deals with Iran,” he said. “But she doesn’t sanction anyone connected with Israel or Israeli companies.”

“So we have dual loyalties here and nobody questions where her loyalties really lie,” Springmann concluded.

Nader Talebzadeh, the renowned Iranian intellectual and journalist who chairs the New Horizon organization, has filed a petition with the Treasury, appealing the decision.

“The consequence of your highly inaccurate and inflammatory allegations have had the result of seriously damaging our reputation, costing us a major loss of business and longtime friendships,” he wrote in the petition.

“The NHC is a forum for free thought and expression of these thoughts,” he wrote. “It is held in Iran because Iran has been the focus of mass demonization since 1979, when Iran announced its sovereignty and freedom from US control.”

In an interview on an Iranian television channel, Talebzadeh said in February the sanctions were planned by “Zionists inside America,” including Treasury Secretary Steven Mnuchin.