Apple told the BBC the bill should be amended to protect encryption.
Police, the government and some high-profile child protection charities maintain the tech – used in apps such as WhatsApp and Apple’s iMessage – prevents law enforcement and the firms themselves from identifying the sharing of child sexual abuse material.
But in a statement Apple said: “End-to-end encryption is a critical capability that protects the privacy of journalists, human rights activists, and diplomats.
“It also helps everyday citizens defend themselves from surveillance, identity theft, fraud, and data breaches. The Online Safety Bill poses a serious threat to this protection, and could put UK citizens at greater risk.
“Apple urges the government to amend the bill to protect strong end-to-end encryption for the benefit of all.”
Several messaging platforms, including Signal and WhatsApp, have previously told the BBC they will refuse to weaken the privacy of their encrypted messaging systems if directed to do so.
Signal said in February that it would “walk” from the UK if forced to weaken the privacy of its encrypted messaging app.
Apple’s statement now means that some of the most widely used encrypted apps oppose this part of the bill.
In 2021 Apple announced plans to scan photographs on people’s iPhones for abusive content before they were uploaded to iCloud but these were abandoned after a backlash. It has now clearly signalled its opposition to any measure that weakens the privacy of end-to-end encryption.