Mr Solana met Iran's top nuclear negotiator Ali Larijani at the Supreme National Security Council building in central Tehran on Tuesday. Journalists were barred from the building.
Speaking on state television after receiving the proposals from Mr Solana, Mr Larijani said they had "constructive" talks and Iran would respond after studying the incentives.
"The proposals contain positive steps and also some ambiguities," Mr Larijani said.
He said more talks were needed about the incentives, which were agreed on by the five permanent UN security council members, plus Germany, at a meeting in Vienna on Friday.
"We hope we will have negotiations and deliberations again after we have carefully studied the proposals," Mr Larijani said.
Mr Solana arrived late on Monday bearing the package that was agreed in talks in Vienna on Friday.
He told reporters at Tehran airport that the West wanted "to start a new relationship on the basis of mutual respect and trust."
The package would "allow us to engage in negotiations based on trust, respect and confidence," Mr Solana said.
Details of the proposals have not been made public, but an early draft indicated that if Iran agreed to abandon uranium enrichment, the world would offer it help in building nuclear reactors, a guaranteed supply of nuclear fuel, and European Airbus aircraft.
The United States has reportedly sweetened the offer by saying it would lift some bilateral sanctions on Iran, such as a ban on Boeing passenger aircraft and related parts, if Iran agrees to an enrichment freeze.
The offer contains the implicit threat of UN Security Council sanctions if Iran continues to insist on enriching uranium, a process that can produce fuel for generating electricity or material for making nuclear bombs.
Iran has so far insisted that as a signatory to the Nuclear Non-proliferation Treaty it is entitled to enrich uranium for peaceful purposes. But the world is suspicious of its nuclear plans because it concealed significant aspects of its program for many years.
Mr Solana is expected to explain the details of the package but go no further.
"This trip is not a negotiating trip. Mr Solana is here just to present the package to Iranian officials," an official at the Supreme National Security Council told The Associated Press.
The EU envoy, who is heading a seven-person delegation, is due to meet Iranian Foreign Minister Manouchehr Mottaki before leaving Iran later on Tuesday.