"We still have time before the 31st of October. We will respond when it will be necessary, before or after the 31st of October," foreign ministry spokesman Hamid Reza Asefi told reporters here.
"The resolution is being examined by the concerned officials and this examination is not yet finished," he said.
"When it is complete, we will say so and give our response to the agency, and we will give our clear and definitive position," he said, adding that formulating a response to the agency was "complex and very delicate".
A week ago, the International Atomic Energy Agency (IAEA) gave Iran until the end of October to clear up widespread suspicions that it is using an atomic energy programme as a cover for nuclear weapons development.
The resolution, passed by the IAEA's board of governors after intensive US lobbying, demands Iran answer all the agency's questions regarding its enrichment activities, provide unrestricted access to UN inspectors and a detailed list of its nuclear-related imports.
Iran fiercely denies it is seeking to acquire nuclear weapons, but its failure to comply could lead to Iran being declared in non-compliance with the nuclear Non-Proliferation Treaty (NPT), with the matter being passed to the UN Security Council.
But despite a string of top officials here already blasting the ultimatum and with little sign that increased IAEA inspections will be allowed, Asefi said it was too early to talk of Iran's increased isolation or the prospect of sanctions.
"But what I can say, generally, is that the Islamic Republic of Iran is sufficiently powerful to continue on its path by drawing on its own capacities," he said.
But he also asserted his belief that the issue had not come to an impasse, and emphasised that the foreign ministry had yet to call for Iran to pull out of the NPT.
A number of hardliners here have already urged Iran's leaders to follow or consider following the path of North Korea, which pulled out of the treaty.
Asefi also confirmed Iran had received a letter from Britain, France and Germany aimed at resolving the stalemate over inspections.
But he dismissed media reports suggesting that the European trio had offered a deal to the Islamic republic in exchange for a "confidence building gesture" from Iran.
Asefi refused to divulge the content of the letter -- sent before the IAEA resolution was passed on September 12 -- but said that the European and US position vis a vis Iran appeared to be "identical".
"We were expecting the Europeans to be independent and take the realities into account," he complained.