Russian site Newsfront released a video on Tuesday in which the hostage, a native of Brescia, appears to call on the Italian government to intervene and prevent his execution.
Sources at the Italian foreign ministry's crisis unit said that Italian authorities had been aware of the video for several days and were following the case.
The video captures Zanotti dressed in a white tunic, kneeling on the ground amid olive trees.
A second man dressed in black and with his face concealed, stands behind Zanotti with a machine gun.
Zanotti is holding a placard with a date on it, which appears to read November 15, 2016.
"My name is Sergio Zanotti," the man says with a Brescian accent.
“And for seven months I have been imprisoned here in Syria. I appeal to the Italian government to intervene for me before I am executed."
Another photo posted on the same site portrays the alleged hostage standing barefoot and holding the same placard shown in the video.
Below the image is that of a passport made out to Sergio Zanotti, born in 1960 in Marone near Brescia.
Following the release of the footage on Tuesday, it was revealed that the Rome prosecutor's office opened a file into the kidnapping months ago.
The case against the unknown individuals for kidnapping for terrorist ends is being coordinated by deputy public prosecutor Sergio Colaiocco.
Italian investigators have traced the hostage's recent movements and have confirmed that Zanotti did indeed leave Italy several months ago for Turkey, where he disappeared.
Zanotti left Italy for southern Turkey for unspecified work reasons but disappeared around mid-April, when he was to have returned to Italy, according to family members.
His ex-wife reported his disappearance to the police.
How the kidnapping occurred and in what context has not yet been clarified and no demand for ransom has been made.
With ANSA
