News: Users found that it was showing only “in favour of leaving the EU” option.
The social networking site came under fire after users found that it was showing only "in favour of leaving the EU" options in updates, but not the other that supports remaining.
The bias was noticed by Berlin-based writer and strategist Jon Worth while he was writing a status update on Facebook, the Guardian reported.
He noticed Facebook showing only a pro-leave option in the list of available activities for uses.
Worth was quoted by the publication as saying: "I cannot imagine many people actually use a Feeling/Activity so deeply buried in Facebook’s menus.
"But what worries me is that Facebook has added this to its app – and this is a core function, not something user-generated – and did not stop to think about the inherent bias shown here.
"Once more it calls into question how neutral privately owned social networks are when it comes to political debate."
Facebook has removed referendum prompts from the list citing sensitivity of the issue, BBC reported.
However, both the options are now displayed for users if they manually enter ‘EU’ in the search bar.
A spokesman of the company rejected allegations that it was influencing "the tone of political debate" on its platform.
Facebook’s spokesman said: "People who search for ‘EU’ when they are using our status tool will see a full range of options enabling them to add if they are thinking of leaving or remaining in the EU.
"People scrolling through the list of activities see options based on what their friends and other people have been using."
The two official campaigns on the referendum- Vote Leave and Britain Stronger in Europe-are also not featured in the list for users.
The social network said that it did not include the campaigns as they were not under the "non-profit organisation" category.
The referendum, which is scheduled to be held on 23 June, will decide whether the UK should remain in or leave the European Union.