The comments from Nicholas Burns, the US under secretary of state, came as he said Washington would be pushing for much tougher sanctions against Iran after the IAEA's report.
Although Washington has said it wants the nuclear standoff resolved through diplomacy, it has not ruled out military action against the country.
But senior Iranian officials have shown little sign of compromise.
Ali Larijani, Iran's chief nuclear negotiator, said on Tuesday that Iran could give the West guarantees that its nuclear programme was peaceful if there were negotiations.
But he said Iran would not shelve the programme as a precondition of talks.
|Iran's president has said he will stop |
enrichment if the US stops too [EPA]
Speaking in Vienna, he said: "Concerns about possible deviations of Iran's activities in the future" can be "settled at the negotiating table.
"We would give necessary guarantees that there will be no deviation ever towards nuclear weapons."
After talks in the Austrian capital with Mohamed ElBaradei, the UN International Atomic Energy Agency chief, Larijani said Iran would not be suspending enrichment activities.
"What should be important to you is to have Iran's activities within the framework of the IAEA and under the supervision of the inspectors of the agency."
Elbaradei himself meanwhile has warned against "hype" over Iran's nuclear activities, saying the country could be five or 10 years from developing a nuclear bomb.
Nevertheless, he told the Financial Times earlier this week, barring an unlikely last-minute turnaround by Iran "I will have to report negatively".
'Force and pressure'
With the US expected to move a second carrier group into the Gulf region shortly, Larijani warned that no attempt should be made to resolve the issue through "force and pressure" saying Tehran would respond to any attacks.
"Iran has the right to develop nuclear energy just like other countries"
Shahid, Delhi, India
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Replying to a question about US pressure on Iran to give up enrichment, Larijani said: "If they ... move into the boxing ring, they would have problems. But if they sit at the chess table, then both sides would come to a result."
Sadegh Zibakalam, a professor at Tehran University, told Al Jazeera on Tuesday that "previous guarantees provided by the Islamic Republic have been kept perfectly".
"Nothing has proved that Iran is doing anything wrong. Guarantees [made by Iran] have been good enough for the IAEA, and good enough for the UN.
"But they have not been good enough for the US. Any sanctions on Iran have been at the behest of the United States.
"If the US was not pursuing hostile actions towards the Islamic Republic, the UN would not impose sanctions."
Speaking on the same Al Jazeera programme, Raymond Tanter, political science professor at Georgetown University and a member of the New York-based Council on Foreign Relations, said: "It is my humble opinion that Iran cannot provide guarantees that it will not deviate towards nuclear weapons."
|"If they ... move into the boxing ring, they would have problems. But if they sit at the chess table, then both sides would come to a result"|
Iran's chief nuclear negotiator
Based on the premise that highly enriched uranium is required to build a nuclear bomb, he said: "Once you can enrich for three per cent, you can enrich for 80 to 90 per cent. All you need is the requisite number of centrifuges."
On Tuesday, Mahmoud Ahmadinejad, the Iranian president, addressing the US, said in front of thousands of supporters at a rally in Gilan province: "There is no problem with your demand for us to close our nuclear facilities.
"But what we say is that if justice is to be performed, you must close your nuclear facilities too."