The United States and Italy on Friday signed an agreement to share their fingerprint databases in a bid to root out potential extremists among migrants travelling to the West.
The "technical understanding", which updates a serious crime accord from 2009, was signed by Italian Interior Minister Marco Minniti and Elaine Duke, acting US Homeland Security Secretary.
The pair were at a G7 interior ministers meeting in Italy dedicated to working out how to deal with a potential flood of foreign fighters returning to Europe after the fall of IS stronghold Raqa in Syria.
The aim was "to ascertain whether they are noted criminal suspects or terrorists", Italy's interior ministry said in a statement.
Minniti has warned fighters fleeing after the fall of Raqa could take advantage of the confusion and "use the human trafficking routes" to return home – raising the spectre of extremists embarking on the migrant boats which regularly head from Libya to Italy.