Britney Spears admits her mother 'slapped so hard' after party with Paris Hilton

Britney Spears declares she would never forget the day her mother slapped her across the face.

The 40-year-old pop star says mom Lynne Spears could not contain her anger when she stayed out too late with her sons.

“The first time I ever got slapped was the one night Paris [Hilton] and Lindsay [Lohan] dropped me off at my beach house with my babies,” Britney wrote on Instagram.

Britney shares sons Jayden James and Sean Preston with ex-husband Kevin Federline.

“My mother was watching Jayden and Preston...yes I partied till like 4am and my mother was P*SSED !!!! I walked in, she looked at me and hit me so hard that I will never forget it !!!”

This comes after Lynne turned in to Britney's comments to apologise for her behaviour towards the singer.