T-Mobile US joined forces with Sprint in a crusade against nuisance calls, launching a caller verification scheme which will work across both networks to identify spam.

Using their respective implementations of the SHAKEN/STIR spam prevention framework, the pair will validate calls originating from one another’s networks before passing them to a consumer’s device. Recipients will see a message on their handset confirming legitimate communications: spam calls which illegally use fake numbers will fail authentication.

In a statement, T-Mobile CEO John Legere noted operators are “in an arms race with these scammers,” adding “we’ve got to join forces as an industry to keep all wireless customers protected”.

T-Mobile previously deployed similar validation schemes with AT&T and Comcast. It noted the service now works across 23 smartphones on its network, an increase from 12 in August 2019.

Sprint announced separately it is also working with Comcast to implement the same technology, with nationwide availability expected “in the coming months”.