According to VentureBeat, Facebook has ended the ability to sign up for Messenger without a Facebook account.

In the past, individuals who wanted to use Facebook Messenger could use their phone number to sign up. In an email to VentureBeat, the social media giant confirmed that ability is now gone.

“If you’re new to Messenger, you’ll notice that you need a Facebook account to chat with friends and close connections,” the email said. “We found that the vast majority of people who use Messenger already log in through Facebook and we want to simplify the process. If you already use Messenger without a Facebook account, no need to do anything.”

As expected with a change this big, VentureBeat is reporting the transition has not been entirely smooth, with some users’ accounts being restricted.

Facebook has made no secret about its desire to integrate its various messaging platforms, including Messenger, WhatsApp and Instagram. The company wants its users to be able to communicate across its platforms. In a post, Zuckerberg emphasized this point:

“**Interoperability**. People should be able to use any of our apps to reach their friends, and they should be able to communicate across networks easily and securely.”

Needless to say, regulators are not exactly thrilled with this approach and there has been talk of the FCC trying to get an injunction to prevent the integration. It will be interesting to see if this move triggers further scrutiny.