Signal president Meredith Whittaker is prepared to withdraw the privacy-focused messaging app from Australia — saying she hopes it doesn’t become a “gangrenous foot” by poisoning its entire platform by forcing it to hand over its users’ encrypted data to authorities.

Ms Whittaker says Signal would take the “drastic step” of leaving any market where a government compelled it to create a “backdoor” to access its data, saying it would create a vulnerability that hackers and authoritative regimes could exploit, undermining Signals’ “reason for existing”.

Pressure has been mounting on Signal and other secure messaging platforms. ASIO director general Mike Burgess has urged tech companies to unlock encrypted messages to assist terrorism and national security investigations, saying offshore extremists use such platforms to communicate.