Italy and Iran signed billions of dollars in business deals on Monday at the start of a visit to Europe by Iranian President Hassan Rouhani aimed to rebuild his nation's ties with the West after years of economic sanctions.

Heading a 120-strong delegation of business leaders and ministers, Rouhani planned to spend two days in Rome before flying to France on Wednesday, in the hope of polishing Tehran's diplomatic credentials at a time of turmoil in the Middle East.

An Italian government source said the Iranians would sign up to 17 billion euros ($18.4 billion) worth of deals in sectors from energy to infrastructure and from steel to shipbuilding.