Iranian President Hassan Rouhani is due to arrive in Italy for the first leg of a European trip during which he is expected to sign major business deals.
The visit comes a week after the implementation of a nuclear deal that saw economic sanctions against the Islamic republic lifted.
In Rome, Mr Rouhani is expected to sign agreements with Italian firms worth some $18bn (£13bn).
On his second stop in France, he is seeking to clinch a major plane deal.
The Iranian president is leading a 120-member delegation that includes government ministers and businessmen for the five days of meetings in Rome and Paris.
In Italy, Mr Rouhani will hold talks with Italian President Sergio Mattarella and Prime Minister Matteo Renzi.
“This is a very important visit,” a senior Iranian official was quoted as saying by Reuters news agency.
“It’s time to turn the page and open the door to co-operation between our countries in different areas,” the official added.
During the second leg in Paris, Mr Rouhani wants to finalise a deal with Airbus for the purchase of 114 aircraft from the European manufacturer.
Tehran is also considering buying planes from US manufacturer Boeing.
Since the 1979 revolution which brought Islamic clerics to power, Iran has struggled to buy planes and spare parts from the West. Passengers in Iranian airports often wait many hours for ageing jets to be fixed.
To ordinary Iranians, the promise of brand new planes will be the most immediate sign so far that the nuclear deal is making their lives better, the BBC’s James Reynolds in Rome reports.
On Saturday, Iran and China signed 17 agreements on a range of issues from energy to boosting trade to $600bn.
International sanctions against Iran were lifted last week after it agreed to roll back the scope of its nuclear activities.