San Francisco: Facebook Inc has enabled users without an account to sign up for its Messenger app with a phone number, the social media company said on Wednesday, in another move to broaden the app's reach and make it a standalone platform.

Earlier this year, Facebook opened up Messenger to developers, and Chief Executive Officer Mark Zuckerberg said he wanted to connect users directly with retailers, restaurants and other businesses.

With the latest update, users will be prompted by an option that says "Not on Facebook?" when they open the app. They can then sign up with their name, phone number and a photo.

The mobile messaging service, which has 600 million users, has added a number of new features in recent months, including games and video calling.

Facebook's flagship social network has 1.4 billion users.