(CNN) -- Tehran announced Sunday that it will allow the family of Robert Levinson, a former FBI agent who disappeared while on a business trip to Iran in March, to travel to Iran.
Christine Levinson: "We believe the Iranian government has the power to assist us."
His whereabouts are unknown, and the Iranian government has said it has no knowledge of his fate. Levinson was last seen on Iran's Kish Island.
The announcement came shortly after the missing man's wife, Christine Levinson, wrote to the Iran's foreign minister, Manouchehr Mottaki, seeking permission for his family to travel to Iran.
"The Iranian government announces its consent to this request even though there is no information that would corroborate the presence of Mr. Levinson in Iran," Iran said in a press release.
"The relevant Iranian authorities have so far made every effort to find any clues as regards Mr. Levinson's case," according to the statement.
"However, as the Swiss Embassy in Tehran [the U.S. Interest Section] has been repeatedly informed, no sign of his presence in Iran has been traced thus far.
"Nevertheless, pursuant to the request made by Mrs. Levinson to travel to Iran, and if this trip may in any way help allay her concern and anxiety as well as those of the Levinson family, the relevant authorities of the Islamic Republic of Iran welcome this trip and will spare no efforts to help them during their stay in Iran."
The announcement coincided with the visit of President Mahmoud Ahmadinejad to a General Assembly meeting of the United Nations in New York.
Before the announcement, Christine Levinson said in a written statement released Sunday to the news media, "It is my greatest hope, and that of our seven children, that Iranian President Mahmoud Ahmadinejad will use his visit to New York to announce what the Iranian government has done to find Bob, and provide any information they have uncovered about what happened to him, where he is now, whether he is in good health, and when he will return home."
She added, "We believe the Iranian government has the power to assist us, and we are praying desperately that Iranian officials will help us end the nightmare we have been living since Bob disappeared over six months ago."
Iran has released three Iranian-Americans in recent weeks after a period of detainment in Iran.
In addition to Levinson, another American is believed to be in Iran. Ali Shakeri, a California businessman, was arrested in May. E-mail to a friend