"We are discussing it. I cannot give you the exact date," the president told reporters when asked to say when Iran would sign the text.
Khatami also reminded reporters that even after Iran signs the accord, it would have to be submitted to the Majlis, or parliament, for approval.
"This is a process like all other agreements. It has to go to the Majlis," he said.
The president was speaking the day after the Islamic republic bowed to International Atomic Energy Agency (IAEA) demands for a stricter inspections regime, full disclosure of its past nuclear activities and a suspension of uranium enrichment.
The president said a decision on the length of time Iran would suspend uranium enrichment was "100 percent in our hands".
"We have agreed to suspend enriching uranium temporarily. We will not give gas to the devices that need gas for the time we see beneficial. In other words we will stop... in order to show our goodwill and show our programme is on a peaceful track," he said.