Story highlights Iranian Foreign Ministry says it is doing its own investigation

Israel says a man admitted to spying for Iran

Israel says the man had photos of U.S. Embassy, other sites when he was arrested

Suspect's attorney says client had no intent to harm Israel

Israel has arrested an Iranian-born man, accusing him of spying for Tehran.

He was carrying photos of various sites, including the U.S. Embassy in Tel Aviv, the Israeli government said Sunday.

The announcement came as Israeli Prime Minister Benjamin Netanyahu traveled to the United States to address the United Nations General Assembly and meet with U.S. President Barack Obama.

Netanyahu has been outspokenly wary of Iran's apparent efforts to improve relations with the West.

"I will tell the truth in the face of the sweet talk and the onslaught of smiles," he said Saturday, in the wake of last week's speech at the U.N. by Iranian President Hassan Rouhani.

According to a news release Sunday from the Israeli government, Ali Mansouri, a native of Iran who has also lived in Belgium, was arrested September 11 at Ben Gurion Airport as he was leaving Israel. He was traveling under the name Alex Mans, the statement said.

"He gave full details about the men that directed him and said they told him to cover up his visits to Iran, after he had been in Israel, where he reported to his directives and received instructions from them. His operatives hoped his Belgium identity would help him get around the security check at the airport," the statement said.

Israel accused Mansouri of working for a special unit of the elite Quds Force

He was plotting to set up a spy network in Israel under the guise of a businessman who marketed services to restaurants and stores, the statement said. Mansouri was promised $1 million, the Israeli government said.

An attorney for Mansouri told CNN his situation "is more complicated than what was introduced by the (Israeli General Security Service)."

"He didn't have any intention to harm Israel and also he doesn't have any anti-Israeli agenda or pro-Iranian agenda," said attorney Michal Orkavi.

Marzieh Afkham, a spokeswoman for the Iranian Foreign Ministry, said the ministry would comment once it finished its investigation into the matter.

A U.S. State Department official, speaking on background, said Washington was aware of the report, but referred CNN to the Israeli government.

Mansouri became a Belgian citizen in 2006, the Israeli government said. They allege he was recruited to become a spy for Iran in 2012.

Rouhani spoke last week at the United Nations on his country's nuclear program, saying Iran is prepared to engage in talks and nuclear weapons have no place in his country's defense structure.

Netanyahu said then that his country "will not be fooled by half-measures that merely provide a smokescreen for Iran's continual pursuit of nuclear weapons."