Users uncomfortable with facial recognition technology would be able to opt out of the feature so their public profile photo would not be included in the facial recognition database.
Egan said Facebook was not using facial recognition technology for any other features, but that could change.
"Can I say that we will never use facial recognition technology for any other purposes? Absolutely not."
But she said if they decided to use it in different ways, they would "continue to provide people transparency" about that and control.
Facial recognition technology has been a sensitive issue for technology companies, raising concerns among some privacy advocates and government officials.
Tag Suggest, which the company introduced in 2011, is not available in Europe because of concerns raised by regulators there, Reuters reported.
Google's social network, Google+, also employs similar technology, but requires users to opt in.
A spokesman for New Zealand Privacy Commissioner Marie Shroff said her office was watching the developments closely, but it would be some time before the technology was rolled out. It was not mandatory and users could opt out, he said.
Facebook was aware of people's privacy concerns and would not implement anything that would drive users away or make them rebel.
"It's one of these developing technologies that we're monitoring closely and we're keeping an eye on the privacy implications. It's something that they're floating as an idea and we noted it with interest," said the privacy spokesman.
Also in its update announcement on Thursday, Facebook amended its Statement of Rights and Responsibilities so that members under 18 years of age were deemed to have affirmed that a parent or legal guardian agreed to allow marketers to use some of their personal information in ads.