Jack Wraith, who chairs the MICAF, said networks had been made "accountable".More info at BBC.
He acknowledged blocking was already commonplace when a phone was stolen but told BBC News: "Currently there is no accountability on networks where blocking phones is concerned.
"The networks are now answerable and they will get named and shamed by us if they fail to stick to the charter.
Operators to block stolen phones

In the future, around 80 percent of mobile phones will be blocked on all five UK networks within 48 hours of being reported stolen.