When Facebook acquired standalone messaging app WhatsApp in February for $16 billion, the future of its own messaging app, Messenger, suddenly became unclear.

Facebook seems to have settled those questions Wednesday: It's making sure Messenger is here for the long haul.

Facebook will soon force all users to send messages through Messenger by eliminating the chat features from its traditional iOS and Android versions of the app, a spokesperson confirmed to Mashable. Facebook has started notifying users of the change, with some in Europe receiving the notification today.

Those users will have two weeks to download Messenger before the service within the main app disappears, according to TechCrunch, which first reported the news.

"Today we are starting to notify people that messages are moving out of the Facebook app and over to the Messenger app," a spokesperson wrote in a statement to Mashable. "To continue sending messages on mobile, people will need to install the Messenger app."

If you have both the main app and Messenger on your phones, you already complete all messaging through Messenger; the messages tab within the main app redirects you. Those who do not are prompted to download Messenger with little pop-ups from the company that highlight Messenger's functionality, but users did not need to download in order to continue messaging their Facebook friends.

Image: Kurt Wagner/Mashable

This update to the standalone app will change that by making Messenger the only way to chat via mobile.

The company will alert users multiple times before the feature disappears, although a timeline hasn't been set for when messaging within the main app will be gone for good. Facebook is starting with a "handful of countries in Europe," according to a spokesperson.

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