The Italian foreign ministry has summoned the American ambassador in Rome for "clarifications" after Italian media reported a U.S. intelligence agency intercepted phone calls by then-Premier Silvio Berlusconi and some of his aides in 2011.

La Repubblica daily and l'Espresso newsweekly reported Tuesday the alleged spying occurred in late 2011, amid international worry over Berlusconi's government's ability to handle a worsening debt crisis. The pressure soon forced Berlusconi to resign.

The reports cited WikiLeaks documents about purported intercepted conversations, which the foreign ministry described as "indiscretions."

Italy and the United States are staunch allies. While premier, media mogul Berlusconi boasted of close ties with Washington.

There was no immediate comment from the U.S. Embassy on the summoning of Ambassador John Phillips or on how the meeting went.