The stunning 54-year-old was seen happily chatting away to the rapper in-between dancing and sipping on champagne at her raucous bash – which was sponsored by his brand Ciroc.

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Fancy seeing you here! Jennifer Lopez was in fantastic spirits as she laughed with ex-boyfriend Sean ‘P Diddy’ Combs at her American Music Awards afterparty sponsored by Ciroc in Los Angeles on Sunday night

Jennifer looked rather taken by the 46-year-old music star’s banter, and he was also full of smiles while clutching a candy lollipop.

The former lovers were, at one point, one of the music industry’s hottest star couples – they previously dated in 1999, around the time J-Lo was putting together her debut album.

Their relationship ended after less than two years, however, when they were arrested over a nightclub shooting in New York in December ’99: Jennifer split from the rapper and quickly went on to marry backing dancer Cris Judd.

But the exes are on good form 16 years on from the incident, and have long been close friends.

Getting giddy! Jennifer, 46, let loose as she clutched a glass of champagne while dancing at her own bash

With her man! Although Jennifer spent time with ex-beau Diddy, she also made sure to lavish her attentions on current boyfriend Casper Smart

Jennifer looked to be having the time of her life as she let loose at the soiree, drinking up the bubbly and dancing with the other revellers at her self-hosted party.

And, in case anybody couldn’t remember where they were, her moniker J-Lo was emblazoned across the big screens inside the club venue.

She also spent time with her boyfriend Casper Smart, who appeared to be taking the evening rather more seriously. The party was sponsored by Ciroc Apple infused vodka and Cross pens.

Weeey! Jennifer raised her hands to the roof as she got the revellers into the party spirit

She’s having a great time! J-Lo could barely contain her giggles as she chatted to boyfriend Casper and a male pal

Ain’t no party like a J-Lo party! The room was packed with the lucky few who had scored a ticket to Jennifer’s party, many of them holding up bottles of champagne

Fancy a sip? Jennifer was rarely spotted at the party without a glass of bubbly in her hand

Entertainment: Music was provided during the swish soiree by rapper Wiz Khalifa

Catching up: Looking like any other scene in a club, Jennifer cosied up to singer/songwriter Shawn Mendes inside the packed venue

Earlier in the evening, Jennifer had gone along to the official after party, hosted by Moet & Chandon, where she bumped into fellow performer Demi Lovato, who had seemingly been inspired by her ensemble.

The Love Don’t Cost A Thing singer donned a embellished crop top, which flaunted her ample cleavage and trim waist.

She teamed the crop top with a black, high-waisted, figure-hugging skirt, accessorising with a pair of glitzy silver earrings and a jazzy ring.

Her blonde locks were pinned back into a stylish updo, while she sported a stunning beauty look consisting of taupe smokey eyes, lashings of black mascara and glossy nude lips.

The mother-of-two also covered up in a stunning bejwelled cape, which she later removed to showcase her outfit in all its glory.

Sexy in skirts: Jennifer had earlier gone along to the official AMAs afterparty, along with copycat Demi Lovato, whose style had seemingly been inspired by J-Lo’s

There she is! And Demi was also welcomed to Jennifer’s party later in the night, and she attended along with Nick Jonas and her boyfriend Wilmer Valderrama

Group shot! Jennifer and Demi stole the limelight as they posed with their boyfriends, and Nick 

After-party fun: Posing with DSQUARED2 founders Dean and Dan Catenacci, the singer – who also hosted the show – donned a embellished crop top, which flaunted her ample cleavage and trim waist

Glam look: She teamed the crop top with a black, high-waisted, figure-hugging skirt, accessorising with a pair of glitzy silver earrings and a jazzy ring

Lovely look: Posing with Paula Abdul, the mother-of-two also covered up in a stunning bejwelled cape, which she later removed to showcase her outfit in all its glory

Fellow performer Demi followed J-Lo’s lead, also wearing a crop top and mini skirt combo.

The US singer flashed her figure in a racy black PVC crop top, worn with a matching pencil skirt with a gold zip running down it.

The Confident star covered up wearing a textured jacket, as well as the same beauty look she was sporting earlier.