US president Barack Obama has condemned as hateful, offensive and inexcusable a suggestion by Iranian president Mahmoud Ahmadinejad of a US government role in the September 11th attacks.
Mr Ahmadinejad also said there may be a meeting next month on his country's disputed nuclear program.
Mr Obama, in an interview with the BBC Persian news service, lashed out at Mr Ahmadinejad for the latest of what the White House called a long list of outrageous comments that would deepen Tehran's isolation from the international community.
"It was offensive. It was hateful," Mr Obama said. "And particularly for him to make the statement here in Manhattan, just a little north of Ground Zero, where families lost their loved ones ... for him to make a statement like that was inexcusable."
The United States and its Western allies are locked in a standoff with Iran over its nuclear program, which Washington believes aims to produce atomic weapons but which Tehran says is for solely peaceful purposes.
Mr Obama decided to sit down for the interview before Mr Ahmadinejad made his 9/11 comments as a way of speaking directly to the Iranian people. BBC Persian is broadcast in Farsi, the dominant language in Iran.
Mr Ahmadinejad, in an address at the United Nations General Assembly yesterday, said it was mostly US government officials and statesmen who believed al Qaeda militants carried out the suicide plane hijacking attacks that brought down New York's World Trade Centre and hit the Pentagon outside Washington.
He said that another theory was that "some segments within the US government orchestrated the attack." He continued to discuss the issue on Friday, calling the background to the attacks "suspicious" during a news conference.
A senior White House official told reporters the remarks were part of a pattern from Mr Ahmadinejad, including denial of the Holocaust, that would further isolate the country and harm the interests of its people.
In Mr Obama's speech at the United Nations on Thursday, he reiterated the US position that the door to diplomacy with Iran remained open but that Tehran must fulfil international obligations over its nuclear program.
Mr Ahmadinejad told a news conference today he was ready for talks with the international community, and that an Iranian official might meet next month with world powers pressuring the country to prove its nuclear program is purely peaceful.
Reuters