The report ran in the weekly newspaper L'Espresso in collaboration with the secrets-exposing organization WikiLeaks.
"The Italian Foreign Ministry has summoned the U.S. ambassador, John Phillips, to clarify the news appeared (in) the press, according to which the Italian Prime Minister Silvio Berlusconi and some of his close collaborators would have been subject to wiretaps in 2011," a ministry statement reads.
The L'Espresso report came as WikiLeaks also publicized documents
that it says shows the NSA had intercepted Italian diplomatic cables about a 2010 conversation between Berlusconi and Israeli Prime Minister Benjamin Netanyahu, as well as communication from a Berlusconi adviser in 2011.
This is among the latest examples of documents, leaked over the last several years, that showed past spying activities by the United States against officials in areas such as France, Germany, the European Union and Brazil.
Among the new WikiLeaks documents is what the organization says is an NSA description of the 2010 Berlusconi-Netanyahu conversation.
In an online statement, WikiLeaks said Tuesday
that the NSA "stole sensitive Italian diplomatic cables detailing how Israel's Prime Minister Benjamin Netanyahu implored Italy's Prime Minister Silvio Berlusconi to help patch up his relationship with U.S. President Barack Obama, who was refusing to talk to Netanyahu."
Among Tuesday's other WikiLeaks releases: Details of what the group says is a 2011 NSA document revealing that it intercepted a Berlusconi adviser's communications about a meeting between the Italian leader, then-French President Nicolas Sarkozy and German Chancellor Angela Merkel.
The document reveals a "a critical private meeting" between the three regarding the Italian financial system and debt problem -- a meeting in which Berlusconi "was told the Italian banking system was ready to 'pop like a cork,'" WikiLeaks said.
"As we have said previously, we do not conduct any foreign intelligence surveillance activities unless there is a specific and validated national security purpose," U.S. State Department deputy spokesman Mark Toner said Tuesday about the reports. "This applies to ordinary citizens and world leaders alike.
"Indeed, (President Barack Obama) has made clear that -- unless there is a compelling national security purpose -- we will not monitor the communications of heads of state and government of our close friends and allies."
Toner added that the United States and Italy "have enjoyed a long friendship based on our shared values and a history of cooperating to advance mutual interests around the globe."
"As allies and partners, we will continue to work closely with Italy to protect the collective security of our two countries and of our citizens," Toner said.