The report said the deal had been signed on 20 May by the government of national unity led by Prime Minister Mario Draghi.
Last year, the US under-secretary of state for economic affairs, Keith Krach, was reported to have warned both Italy and Germany to reconsider the use of Huawei gear in their 5G networks.
Washington has campaigned for close to three years to try and push countries it considers allies to avoid using 5G equipment from Huawei in their networks.
The Chinese company has suffered heavy losses as a result. It denies that its networks are in any way less secure than those of its rivals.
Comment has been sought from Huawei Australia.