By Eleanor Gower for MailOnline
Published: 11:19 EST, 29 September 2014 | Updated: 11:55 EST, 29 September 2014
They are known both for their distinctive singing voices as well as their onstage racy ensembles.
But Rihanna and Christina Aguilera looked a little more demure as they dined together at upmarket restaurant Giorgio Baldi on Sunday night.
The Diamonds singer joined Christina and her fiancé Matthew Rutler at the eatery, in Malibu, California with Christina sporting a distinctive cream hat with black ribbon.
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Dining with friends: Rihanna and Christina Aguilera enjoyed dinner together at Giorgio Baldi on Sunday night
Over what appeared to be red wine and candlelight, the singers looked immersed in conversation although Rihanna took time to check her cell phone at times.
She arrived dressed looking casual in a black mini dress, black sneakers and a black and white coat while Christina sported a cream hat with a black ribbon.
The singer was enjoying a break from looking after her new baby Summer Rain who she welcomed around six weeks ago.
Girly chat: Rihanna can be seen immersed in conversation with Christina, while her fiancé Matthew Rutler looked on
Texting over dinner: Rihanna coudn't resist looking at her phone over the Italian meal
Taking a sip: The singers appeared to be drinking red wine with their dinner
Casual arrival: The Diamonds singer sported a black mini dress, black sneakers and a black and white coat
The star is already mother to six-year-old Max Bratman by her ex-husband Jordan.
The star has been displaying a slim post-pregnancy figure recently which a source credited to yoga.
'She is very dedicated to yoga,' the insider told E! News. 'So much that she has never stopped practising it. She did yoga the entire time she was pregnant.
'And Christina has already been working hard on getting her bod back in shape! She is doing private yoga sessions and loves how it makes her feel.'
Hats off: Christina and Matthew arrived with a bodyguard driving the car and the singer in the back seat
Animated: The stars looked in high spirits over the meal
Casual mode: Both stars were looking a little more demure on Sunday night
Fine dining: The upmarket Italian restaurant is a favourite of Rihanna
Although they did not perform together, Rihanna and Christina's separate raunchy appearances on the 2010 finale of the UK X Factor drew 3,215 complaints - the most any programme received that year.
Christina's rendition of Express from her film Burlesque caused the most upset, with viewers left shocked as she did the bump and grind with her female dancers.
The talent show was accused of straying somewhat from its family viewing credentials with the pair putting on two extremely provocative pre-watershed performances.
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