Police officers in Australia are being investigated after Lily Allen tweeted a picture of herself in handcuffs upon her arrival in the country.

The 'Smile' singer flew into Coolangatta Airport on the Gold Coast over the weekend to headline the Splendour in the Grass music festival and reportedly asked police to handcuff her so she could take a picture to post on Instagram.

The image - which was captioned ''#uhoh'' and has since been deleted - shows Lily on her knees with her hands cuffed behind her while a police officer stands over her.

However, superiors did not take the joke lightly and the Australian Federal Police have launched an investigation into what happened.

A source told TMZ: ''[An investigation was launched and the AFP] acknowledged protocols were breached but then seemed to justify it by saying the officers were caught in the moment.''

In the picture, which was shared by fans on Twitter and Instagram, Lily is dressed in jeans and a dark top with her dyed red hair pulled back.

Both she and the uniformed policeman appear to be smiling.