Selena Gomez and sister Gracie plant kisses on Nicola Peltz’s cheeks as they ring in her birthday

‘It’s not your birthday yet, but let’s celebrate now’: Selena Gomez and her sister Gracie plant twin kisses on Nicola Peltz’s cheeks as they celebrate the actress’ 28th birthday

They have become best friends in recent months.

And Selena Gomez and Nicola Peltz stepped out this week to celebrate ahead of Nicola’s 28th birthday on Monday.

The singer, 30, and the actress, 27, posed for a new set of stunning snaps on Instagram on Sunday.

Close friends: Selena Gomez and Nicola Peltz stepped out this week to celebrate ahead of Nicola's 28th birthday on Monday

Close friends: Selena Gomez and Nicola Peltz stepped out this week to celebrate ahead of Nicola’s 28th birthday on Monday

The photos showed Selena and her little half-sister Gracie kissing Nicola on the cheeks.

Nicola and Selena were twinned in matching black suits, their long tresses pulled up into elegant chignons.

Nicola, daughter of billionaire businessman Nelson Peltz and model Claudia Heffner, smiled as she received a kiss on both cheeks.

She sported a face full of bright makeup that included heavy black eyeliner and a layer of pink blush.

Best friends: The singer, 30, and the actress, 27, posed for a new series of stunning snaps on Instagram on Sunday.

Best friends: The singer, 30, and the actress, 27, posed for a new series of stunning snaps on Instagram on Sunday.

Captioning the affectionate photos, Selena wrote, “It’s not your birthday yet, but let’s celebrate NOW.”

The duo’s unexpected friendship has been going from strength to strength recently, and the pair even got matching ‘angel’ tattoos.

They showed off their new ink on Instagram Monday during a sun-kissed New Year’s trip to Los Cabos, Mexico.

The duo were dressed in their glamorous party outfits when they took a photo of the matching tattoos found on their arms.

Loving: Photos showed Selena and her little half-sister Gracie kissing Nicola on the cheeks

Loving: Photos showed Selena and her little half-sister Gracie kissing Nicola on the cheeks

Birthday celebrations: Captioning the affectionate photos, Selena wrote: 'It's not your birthday yet but let's celebrate NOW'

Birthday celebrations: Captioning the affectionate shots, Selena wrote: ‘It’s not your birthday yet, but let’s celebrate NOW’

Selena insisted that she and married couple Brooklyn Beckham and Nicola be called ‘a threesome’ when she shared a snap of the trio snuggling up during their trip.

The My Mind & Me star snuggled up with the actress and former model, 23, in an Instagram snap posted on Sunday.

It comes two months after Selena’s notorious falling out with her former friend, Francia Raisa.

The Disney star was seriously ill with lupus when fellow actress Raisa, now 34, offered to donate her kidney and they underwent the difficult transplant process in 2017.

Gomez detailed her health problems in her documentary, My Mind & Me, released in November, but did not mention Raisa.

In an interview in Rolling Stone in November, Gomez named Taylor Swift as her only celebrity friend in the industry at the time. (Raisa is a Latina actress with a number of television and film credits, including Bring It On: All or Nothing, The Secret Life of the American Teenager, and Grown-ish.)

Coincidence: The duo's unexpected friendship has been going from strength to strength recently, and the pair even got matching 'angel' tattoos

Coincidence: The duo’s unexpected friendship has been going from strength to strength recently, and the pair even got matching ‘angel’ tattoos

Francia unfollowed Gomez on Instagram following the documentary’s release and was so upset by Gomez’s quote about Swift that she called it “interesting” in the comments section of an E! News publication.

And on Sunday, Gomez left a surprising comment under a TikTok video that discussed how her Raisa unfollowed her after being rejected in the documentary.

“Sorry I didn’t mention everyone I know,” Selena wrote in the comments, surprising her fans in the process. France has since removed her comment. Meanwhile, Gomez still follows her on Instagram.

New Best Friends: Comes two months after Selena's notable falling out with her former friend, Francia Raisa

New Best Friends: Comes two months after Selena’s notable falling out with her former friend, Francia Raisa