In an interview with the Financial Times published on Thursday, he also said he wanted Italy to become a "facilitator" between Iran and the United States to improve dialogue between the two countries.
"Italy will push forwards to be really in the club on Iran," he was quoted as saying. "Italy will not be left isolated by a restricted group of European partners plus the United States."
The five permanent members of the U.N. Security Council and Germany are trying to get Iran to abandon its uranium enrichment programme.
The United States accuses Iran of wanting to develop nuclear weapons. It also says it is fomenting violence against U.S. soldiers in neighbouring Iraq. Iran denies the charges.
Frattini, former justice and security commissioner for European Union, said he wanted to capitalise on Italy's close commercial ties with Iran but declined to say whether it would support specific sanctions against that country's energy sector.
Italy's energy giant Eni is a big investor in Iran.
In contrast to his predecessor as foreign minister, Massimo D'Alema, Frattini ruled out dialogue with Hamas as long as it kept waging violence against of Israel.
He supported the Dalai Lama's approach to autonomy for Tibet and wanted to maintain an arms embargo on China. Frattini became foreign minister after Silvio Berlusconi won a third term as prime minister in a strong electoral victory against the centre-left last month. (Reporting by Gilles Castonguay, edited by Richard Meares)
