Iranian Parliament Speaker Ali Larijani yesterday said US president-elect Barack Obama's words on Iran's nuclear issue are "unacceptable", the official IRNA news agency reported.

"This is the same erroneous policy of them (Westerners) in the past," Larijani said, adding that "Obama must give true signals of change to the people of the region."

"Obama can understand that change does not only mean a change of color and superficial differences, but also it must have a strategic basis," he was quoted as saying by Iran's English language satellite channel Press TV.

Addressing his first press conference since Nov. 4 election, Obama also said in Chicago on Friday that Iran's development of nuclear weapon is "unacceptable."

The United States and its allies have accused Iran of trying to develop nuclear weapons under the cover of a civilian nuclear program. Iran denies the charges and insists that its nuclear program is for peaceful purposes only.

Iranian President Mahmood Ahmadinejad sent a congratulatory letter to Obama following his historic victory on Tuesday.

Obama confirmed that he had received the letter from Iran's president and said that "I am aware that the letter was sent. I will be reviewing the letter from President Ahmadinejad and we will respond appropriately."