"We have the greatest respect for law enforcement, and we don't design our security improvements to frustrate their efforts to do their jobs", Apple told Reuters.
Apple will make a method - often used by police - for getting data off iPhones much less powerful with a software update announced Wednesday.
Apple is changing settings in iOS that will help prevent devices used by law enforcement and hackers from unlocking iPhone models.
The update could reignite tensions between Apple and the USA government, which wants technology companies to include backdoors - official ways to get around encryption and other security measures - on their devices.
The transition to iPhones using USB Type-C cables has begun.
It comes as a big annoyance to many users, but Apple remains the technological trendsetter, and despite usually not being first, a technology never really arrives until Apple adopts it. In an upcoming version of iOS (likely iOS 12), Apple will include a feature known as USB Restricted Mode which limits access to a locked iPhone through its USB port.
Forensic companies that once employed machines to break through security provisions will now have only an hour to run code on the devices.
Currently, law enforcement and others can plug specialized tools made by cybersecurity experts into the phone's Lightning port to access data. In a case that made plenty of headlines in 2016, it refused to help the Federal Bureau of Investigation get into a phone that mass shooter Syed Rizwan used before he and his wife killed 14 people and wounded 22 others in San Bernardino, California.
The practice has spread in recent years, with law enforcement agencies around the world buying devices that can pull information off a locked phone. In Grayshift's case, the company has been offering a box-like device called GrayKey that can hook up to an iPhone and hack it within a few hours to several days.