The outgoing head of the Federal Communications Commission said a massive Chinese-linked cyber-espionage operation against U.S. telecoms firms known as "Salt Typhoon" is a "clarion call" to address significant telecommunications security issues.

The Federal Communications Commission (FCC) has ordered U.S. telecommunications carriers to secure their networks following last year's Salt Typhoon security breaches.

The State and Treasury Departments say Chinese cybersecurity vendor Sichuan Juxinhe is behind the hacks into numerous US telecommunications companies.