A senior Iranian official has said that direct Iran-US talks about security in Iraq will have an impact on the dispute over Iran's nuclear programme.
Mr Larijani said talks could help calm tensions in the region
Senior nuclear negotiator Ali Larijani said the talks on Iraq could not be separated from the nuclear issue.
He suggested they were a chance to ease tension in the region.
The US has been calling for tougher sanctions against Iran for its refusal to abide by a UN resolution urging it to stop enriching uranium.
Mr Larijani is due to discuss the nuclear issue with the European Union foreign policy chief, Javier Solana, on Thursday.
On Monday, Iran and the US met for public bilateral talks for the first time in 27 years, but the agenda was limited only to the security situation in Iraq.
While much of the hardline media in Iran has been playing down the importance of the talks with America, Mr Larijani said the talks were obviously not a tiny event in the region or the world.
"We have said the nuclear issue and the Iraq talks are two different things but in the political world you cannot really separate them," Mr Larijani said.
"The US-Iran talks will have some impact - what's happened has alerted all the countries of the world that they can use this opportunity to help calm the region."
Mr Larijani said if the Americans acted prudently they could benefit from Iran's proposals on Iraq, but if they made a huge noise in the media than nothing would be achieved.
Mr Larijani was speaking at the airport on his way to Spain for talks with the EU foreign policy chief Javier Solana, to see if there is any room for fresh negotiations on the nuclear issue.
Mr Larijani ruled out suspension of enrichment - a key demand of the United Nations - as a precondition for negotiations.
He also insisted that suspension of enrichment was not a solution to the nuclear issue.
Mr Larijani said Iran was ready for constructive talks but would not accept preconditions and had none of its own.
Mr Larijani said Iran "is ready to implement mechanisms to alleviate other countries' concerns over the nature of its nuclear programme".
UN resolutions demand that Iran halts enrichment, a process which some countries say is a prelude to building atomic bombs.
Tehran denies the charge, saying its nuclear programme is purely for peaceful purposes.
The UN Security Council has imposed two sets of sanctions on Iran for its resistance to UN demands, and some Western powers are pushing for greater penalties.
Iran says it is entitled to enrich uranium as a signatory to the international nuclear non-proliferation treaty, the NPT.