The official White House Instagram page associated with former US President Barack Obama was hacked, according to a Monday report by entertainment news outlet TMZ.

The breach was discovered on Sunday after several unusual posts appeared on the account, which uses the handle @obamawhitehouse.

The most prominent post was an AI-generated image accompanied by a caption that translated as: "The White House is under Shiites' control," according to TMZ.

The hacker also reportedly posted new Instagram stories on the account, which has 2.4 million followers.

A representative for Meta, which owns Instagram, confirmed the breach to TMZ and said the account has since been secured.

All unauthorised content has also been removed.

According to TMZ, the last legitimate post on the account was published January 20, 2017, the day President Donald Trump was inaugurated.

No details have been released about who was responsible for the hack.

Obama maintains a separate personal Instagram account under the handle @barackobama, which has 42.2 million followers.