Discussion about relations has been encouraged by Washington saying it is considering opening a diplomatic outpost in Tehran.
Washington has not had relations with Iran for 30 years and is now embroiled in row over Tehran's nuclear ambitions. But some U.S. commentators say a new U.S. administration needs to break with the past and engage to solve that and other rows.
In Iran, officials have been facing frequent questions about whether they would let Washington establish an interest section and whether a request by an Iranian-American non-government organization to open in Iran would be approved.
"This dispute (with America) is beyond differences of opinion on a few political issues," Supreme Leader Ayatollah Ali Khamenei, who has the final say in all matters of state, was quoted by state TV as saying.
"He said the Iranian nation's hate for America was deep and added the reason for that was the different plots of the American government against the Iranian country and nation during the past 50 years," state TV reported.
Although Khamenei and Iranian officials often lambast the United States, the timing a week before Americans go to the polls suggested the leader was sending a message, analysts said.
"What he is actually doing is putting an end to the discussion that has been going on in the country sparked by the idea of opening an American interests section and the possibility it can create a thaw," said one political analyst.
"Second, Iranians have been watching the American election closely, and this sends a clear message to everyone that whatever happens, that is not going to have any effect on the way Iran views the United States," he added.
Another Iranian analyst said Khamenei's message mainly seemed for home consumption but could also reach "the next American government, that the only way they can have relations with Iran is to create fundamental changes in policies."
Dealing with Iran has been a major foreign policy issue in the U.S. campaign. Both candidates, Democrat Barack Obama and Republican John McCain, have said they would toughen sanctions. Obama says he is prepared to engage in direct talks with Iran.
Washington has expanded sanctions on Iran, which it accuses of seeking to build atomic bombs, despite Iran's denials. It has also been leading efforts to strengthen U.N. measures. The U.N. Security Council has imposed three rounds of sanctions so far.
U.S. officials have said the idea of an interests section — involving sending U.S. diplomats to Iran for the first time in three decades — was aimed to reach out to Iranians by showing any differences were with the government not Iran's citizens.
(Reporting by Zahra Hosseinian; writing by Edmund Blair; editing by Alison Williams)
