Iran declined to confirm a news report on Tuesday that it had appointed an ambassador to Egypt, which would mark the restoration of diplomatic relations after more than 30 years.
"The news regarding the appointment of an ambassador is guesswork and is hasty," Foreign Ministry spokesman Ramin Mehmanparast said at his weekly news conference.
Egypt's foreign minister said earlier this month that Cairo was ready to re-establish diplomatic ties, signalling a shift in Iran policy since the fall of President Hosni Mubarak.
The website of Iran's Press TV reported that Tehran had already appointed its envoy, naming him as Ali Akbar Sibuyeh, a career diplomat who is the son of a senior cleric.
Ties between the countries -- among the largest and most influential in the Middle East -- were severed in 1980 following Iran's Islamic revolution and Egypt's recognition of Israel.
Cairo has long been an ally of the United States and Israel but since Mubarak was toppled by a popular uprising there have been signs of warming between mainly Sunni Muslim Egypt and predominantly Shi'ite Iran.