Britney Spears threw a skateboard-themed birthday party for her sons at the weekend.

The 'Toxic' hitmaker's boys Preston and Jayden - who she has with ex-husband Kevin Federline - turned nine and eight respectively over the weekend and they celebrated their big days with a special bash at their home.

Posting a picture of the boys in front of a table of sweet treats and a birthday banner, newly-single Britney wrote on Instagram: ''Happy Birthday to my two little baby boys. They are growing up too fast!!!''

The former 'X Factor' judge served skateboard-themed food to her sons' party guests, with the treats on offer including skateboard and helmet cake pops and krispie wheels.

Britney's sister Jamie Lynn Spears shared another picture from the party, showing the boys receiving a hug from their mother.

She wrote: ''Happy Birthday Jay-Jay and Preston!! Wish we were there!! Love y'all!!(sic)''

Last week, Kevin - who has four other children from other relationships - revealed his sons had been having skateboarding lessons and it had quickly become a ''passion'' of Preston's.

Posting a video on Instagram of the pair showing their skills, he wrote: ''Thanks @stevebadillo @skatelab for teaching my kids how it's done. Look forward to many more lessons. Preston found his passion... #skatelab (sic)''