Orange bikini Kim Kardashian holidays with sister Kourtney and nephew Mason in Mexico

Kim Kardashian has been spotted sporting an eye-catching halterneck orange bikini as she hit the beach with older sister Kourtney and her two-year-old nephew Mason on a recent holiday to Mexico.

Kim Kardashian, 31, was not content to just spend the day sunbathing – instead trying her hand at bodyboarding in the warm sea.

And she certainly seemed to be taking to the sport like a duck to water, laughing as she cruised in to shore on her bright yellow board.

Kim Kardashian later let her hair down for a stroll down the beach, and looked pensive as she shielded her eyes from the sun.

The reality star later joined sister Kourtney and nephew Mason, carrying the little boy as she splashed around in the water.

At one point, Kim and Kourtney swung delighted little Mason along on the sands.

Mason was dressed in black swimming trunks and a black hat with orange detail which matched his auntie Kim Kardashian’s swimming costume.

Kourtney Kardashian meanwhile, dressed her growing baby bump in a black swimsuit and sheer patterned wrap.

She kept herself protected from the sun in a straw colored hat with black ribbon.

The sisters were in Mexico to celebrate Kourtney Kardashian’s 33rd birthday last month, but were without Mason’s father Scott Disick.

However, the sisters were also joined by her friend Robin Antin who also tried her hand at bodyboarding.

Robin Antin, an entrepreneur, actress and choreographer, who founded girl group The Pussycat Dolls, wore a patterned blue and purple bikini to splash around in the surf.

Kim Kardashianis regularly seen at the gym near her home on Los Angeles, and the results were clear to see as she displayed her washboard stomach and toned legs.

She admitted last month that she is working out up to six times a week to keep her famous figure in shape and has been changing her diet for the better.

Kim Kardashian wrote via Twitter: “I’ve been trying to change my bad eating habits – slow process but its working. I feel so much better! Sugar, dairy & gluten free. HARD!”

She added: “I will have sweets every once in a while & dairy but this is a huge step for me! Its a lifestyle change but I’m loving it so far!”

Kim Kardashian clearly appreciated the break, while divorce proceedings from estranged husband Kris Humphries are still ongoing.

She yesterday spent three hours at her lawyer’s Los Angeles home.