Updated 11:16 a.m. ET
When delegates arrived at the Group of 20 Summit in St. Petersburg, Russia, in September, they were given gifts that included teddy bears, diaries, phone chargers and USB drives.
According to reports in Italian media, the electronics were bugged.
If true, the claims put a new context onover there. The claims also come at a time of tensions between the U.S. and Russia over Syria and other issues.
Russia has denied the Italian media reports, calling them a distraction.
"We do not know what sources this information may have come from, but clearly it is nothing else but an attempt to divert attention from objective problems, which dominate the agenda between the European capitals and Washington, to some ephemeral, non-existent ones," presidential spokesman Dmitry Peskov said on Tuesday, according to RT.com.
On Wednesday, European Commission spokesman Frederic Vincent said the EU was investigating the devices and that initial "analysis of hardware and software have not amounted to any serious security concerns," the Associated Press reports. He added the investigation had not yet been fully completed.
The reports in two Italian newspapers, La Stampa and Corriere della Sera, quote anonymous diplomatic sources as saying European Council President Herman Van Rompuy became suspicious of the electronic gifts he received at the G-20 summit, so he had German security services check them out.
They were discovered to have been loaded with the equivalent of Trojan malware, and possessed the capability of gleaning sensitive information without detection from mobile phones and computers, according to the reports.
Van Rompuy then sent a secret memo to G20 delegates, warning: "The USB pen drives and the recharging cables were able to covertly capture computer and mobile phone data."
The reports do not say how much, if any, data was stolen by the devices.
Since the beginning of the outrage over NSA's alleged widespread spying activities, many have been quick to point out America isn't alone in attempting to eavesdrop on so-called friends. The Italian media reports, if true, only further verify that already .