“Iran has given its answer to the offer with a positive view… “said chief nuclear negotiator Ali Larijani.
Mr Larijini repeated Iran’s call for serious talks, although on the date it said it would submit its answer.
“We have paid attention to the whole offer with a view to solving all the issues," he told the official IRNA news agency.
The United States and Germany, two of the six states proposing the offer, have expressed dissatisfaction with Iran's response.
Under the deal, Iran was offered trade and technology incentives to stop nuclear work.
Iran's reply has not been made public but German Chancellor Angela Merkel said today: "We cannot be satisfied with it.”
"What we expected is not stated there, namely: 'We will suspend our uranium enrichment and come to the negotiating table'."
Iran says it has the right to enrich uranium under the nuclear Non-Proliferation Treaty (NPT).
Washington earlier said the offer of serious talks fell short of UN demands.
Western diplomats say Iran should halt uranium enrichment until it can prove its atomic work is peaceful.
"In our answer, we have answered seriously and fairly to all those offers, including the rights and responsibilities in the framework of the NPT," Larijani said.
"In addition, in the field of long-term technical cooperation and Europe's energy supply security, Iran has given its answer with a positive and logical view."
The incentives included the offer of an energy partnership between Iran, the world's fourth largest oil exporter, and the European Union, as well as other willing partners.
"In another part of the reply, Iran has also paid attention to the issue of regional security, which the (six powers) are interested in," Larijani said.
"Iran, considering the sensitive situation of the region, is ready to help the establishment of a permanent peace," he added, without elaborating.
The UN Security Council says Iran has until August 31 to stop nuclear work or face possible sanctions.
Meanwhile, Iran has assembled and is testing 15 sophisticated P2 centrifuges which can speed up uranium enrichment, the process which makes nuclear fuel or atom bomb material, an Iranian opposition group said today.
The National Council of Resistance of Iran said it had also located what it called a secret production site for the equipment near Tehran.
The claim was made at a news conference in Paris.
Having P2 centrifuges - more sophisticated than P1 versions - would give Iran an increased capability to enrich for nuclear fuel or atom bomb material.
"According to information obtained ... at least 15 P2 centrifuges have been assembled so far and are being tested," said the NCRI's Mohammad Mohadessin.
He said the production site was off a main road north-east of Tehran.