Elle Fanning fainted at the Cannes Film Festival this week

According to Variety, the 'Maleficent' actress was next to her sister Dakota Fanning when she fell, and her sibling helping her to her feet before security led them away.

It's said Colin Firth - who was seated nearby - quickly got to his feet and offered assistance to Elle.

The star later addressed the incident on social media, insisted she was "all good" and putting the blame on both her tight dress and feeling under the weather because of her "time of the month".

She wrote on Instagram: "Oops, had a fainting spell tonight in my 1950's Prada prom dress but it's all good!! #dresstootight #timeofthemonth (sic)"

Although her sister helped her out this week, Elle previously admitted she refused to watch Dakota in 'Friends' because she missed out on a role in the sitcom when she auditioned to be one of the triplets Lisa Kudrow's Phoebe has as a surrogate for her brother, Frank Jr. (Giovanni Ribisi).

She wouldn't even watch the show when Dakota, 25, appeared in an episode in the final season of the classic 1990s sitcom as Mackenzie, a young girl who befriends Joey (Matt Le Blanc) when he looks around Monica (Courteney Cox) and Chandler's (Matthew Perry) prospective new house.

She said: "I had an [audition] to be on 'Friends' once. I might be remembering this wrong but I think I was gonna be one of Phoebe's triplets. I auditioned for it but I didn't get it and I was like, 'I'm boycotting the show, I'm never watching this again.'

"Then my sister was on it and I refused to watch the episode. I was like, 'I am not watching this!' "