Updated 3:30 p.m. ET: White House spokesman Jay Carney would not confirm the letter or overtures for direct talks with Iran when asked in a news briefing on Wednesday, NBC News reported.
"We don't discuss specific communications -- diplomatic communications. I would say that we have a variety of channels through which we can communicate with the Iranians. And that any message we communicate to the Iranians about these issues is -- would be entirely consistent with what we've said publicly, what I've said publicly, the president, secretary of state and others."
Original story: An Iranian lawmaker claimed Wednesday that President Barack Obama called for direct talks with Iran in a secret letter to the Islamic Republic's supreme leader that also warned Tehran against closing the strategic Strait of Hormuz.
Obama administration officials denied to The Associated Press there was such a letter. A report in The New York Times on Jan. 12 quoted unnamed U.S. government officials as saying a similar letter had been sent.
Iran has threatened to close the waterway, the route for about one-sixth of the global oil flow, because of new U.S. sanctions over its nuclear program.
Conservative lawmaker Ali Motahari revealed the content of the purported letter days after the Obama administration said it was warning Iran through public and private channels against any action that threatens the flow of oil from the Persian Gulf.
"In the letter, Obama called for direct talks with Iran," the semiofficial Fars news agency quoted Motahari as saying Wednesday. "The letter also said that closing the Strait of Hormuz is (Washington's) red line."
"The first part of the letter contains threats and the second part contains an offer for dialogue," he added.
Iran's Foreign Ministry spokesman Ramin Mehmanparast confirmed that Tehran received the letter and was considering a possible response.
In Washington, an Obama administration official denied that Obama sent a letter to Ayatollah Ali Khamanei, saying communication of U.S. views were being delivered through other diplomatic messages. The official spoke on condition of anonymity because of the sensitivity of the issue.
U.S. forces are fully prepared to deal with any Iranian threats to close the Strait of Hormuz, Defense Secretary Leon Panetta said on Wednesday.
"We are not (taking) any special steps at this point in order to deal with the situation,'' Panetta told reporters at the Pentagon, Reuters reported. "Why? Because frankly we are fully prepared to deal with that situation now.''
The Associated Press and Reuters contributed to this report.
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