'Close Friends' and 'Acquaintances' lists were rolled out to Facebook last autumn as a way for users to set which of their Facebook contacts were close friends and which were just casual acquaintances.
The move meant that users could receive more posts in their news feed from their close friends, and fewer from people they don't know as well.
In a blog post, Facebook engineer Jonathan Coens said that a new tool has now been introduced that makes it easier to add friends to the Acquaintances list.
"When you add friends to your Acquaintances list they won't be unfriended or notified. You'll just see fewer of their posts in news feed," he wrote.
The move is part of Facebook's attempt to more accurately reflect the different 'shades' of relationships that people hold with each other.
Users with massive lists of 'friends' are now able to sort out who they want to hear from the most, while not completely 'unfriending' those who they don't.
The initiative follows the launch of the Facebook Subscribe button last year, which enabled users to receive the updates of journalists and commentators without actually adding them as friends.
The latest update makes it quicker and easier to relegate friends to the Acquaintance list. The new tool offers a list of suggested contacts to shift to the status, based on the lack of interaction in the past.
The tool is available through the Friends page by selecting the Acquaintances list and clicking 'See All Suggestions'.
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