In a bid to improve security on Facebook, the social networking website is asking each of its more than 900 million active users to provide it with their mobile phone numbers.

The move comes in the wake of much-publicised password hacks at other networking sites including LinkedIn and eHarmony, the Daily Mail reported.

Millions of Facebook users have already seen a link at the top of their desktop news feed requesting them to follow simple security tips.

Those that click on the link are led to the site’s security page, where they are asked to pick a unique password and given a tutorial on how to spot an online scam.

They are then requested to provide their phone number for secure account recovery.

This, Facebook claims, works because when a user confirms their phone number it allows the site to automatically wipe their password in the event of their account being hacked.

The social network would then send a text message to the user informing that their password has been changed.

This, the site reasons, would be preferable to sending the user and email because many of these are ignored as assumed junk and get deleted.

Facebook said the desktop security message, already seen by millions of users in the U.S., will be on all accounts in the next few days.