Valeria Collina, 68, lives in the small town of Fagnano di Valsamoggia near Bologna, and told investigators she didn't know much about her son's life in Britain although she thought he had a regular job.
Collina said her son had been caught up in the wrong crowd while living in the east London suburb of Barking, and that she knew “from a single glance” that he had been radicalised.
"He never let anyone influence him before, neither in Italy nor in Morocco, where he studied computer science at the University of Fez," she said in an exclusive interview with Espresso magazine.
The distraught mother said her son called her two days before the attack, and that she later realised he was calling to say goodbye.
"Although he didn't say anything in particular, I could feel it in his voice," she said.
“We joked about how he would greet me at the airport in London. I was due to go there in ten days to celebrate the end of the month of Ramadan.”
Collina cooperated with authorities when her son was detained by Italian police in March 2016, as he attempted to travel to Istanbul from Bologna airport.
Police stopped Zaghba because he was only carrying a one-way ticket and a backpack, and they suspected he intended to reach Syria via Turkey to join ISIS.
Zaghba was investigated but no charges were laid due to insufficient evidence, and he later moved to London.
His details were, however, uploaded to a Europe-wide database of potential foreign fighters after the incident at Bologna airport, and British authorities were reportedly tipped off about his activity.
Zaghba's mother also said her son was monitored by Italian intelligence ever since.
"In the past, even before he tried to take that flight, he showed me a few videos on Syria," his mother said.
"But he never spoke about going there to fight; for him, Syria represented a place where it was possible to live according to a pure Islam."
Although a practicing Muslim, Collina expressed support for the imams who refused to say funeral prayers for her son, saying it was the “right thing to do”.
"It’s necessary to give a strong political signal, a message to the families of victims and to non-Muslims," she added.
Collina converted from Catholicism to Islam 26 years ago when she married Zaghba's father, a Moroccan national.
The separated couple also have a daughter, Khaoutar, who lives in Bologna.
Collina moved back to Italy with her children two years ago, while her former husband still lives in Fez, where Zaghba was born and raised.
With ANSA