Instagram has unveiled a private messaging service that lets people send photographs and videos to selected friends or groups.
Instagram Direct also allows the 150million users of the picture-sharing app to have private text conversations for the first time.
Until now, material could be shared only publicly.
The announcement was seen as an attempt to rival picture messaging service Snapchat, which lets users send pictures that are erased after a few seconds.
Last month, Snapchat was reportedly the subject of a £1.8billion offer from Facebook, which bought Instagram in a deal worth more than £600million last year.
Announcing the service in New York, Instagram co-founder Kevin Systrom said: ‘We’re super excited to be able to send this out to the world.’
Instagram Direct allows users to send a photo or video to up to 15 people. Recipients receive notification when a message arrives.
Material can be sent to anyone signed up to the service. Photos and videos from the recipients’ followers appear immediately in their inbox, while those from others will open only when a request has been accepted.
‘Instagram is becoming a platform for communicating with other people that is indispensable,’ Mr Systrom said.
Instagram Direct comes as rival social network firms attempt to take control of the demand for picture messaging.
Writing on TechCrunch, Josh Constine said: ‘Founders of Instagram’s competitors might feel flattered today but they should probably be worried too.’