Reality TV star Kim Kardashian West. Picture: Instagram

Kim Kardashian West has apologised for using offensive language at a party.

The 38-year-old reality star - who has kids North, five, Saint, two, and nine-month-old Chicago with husband Kanye West - has confessed that using the word "retarded" at Kendall Jenner's Halloween bash was a "mistake".

In a statement, Kim said: "I want to apologise for what I said in a recent video post that is inappropriate and insensitive to the special needs community.

"I try to learn from my mistakes and this is one of those times. Please know that my intention is always pure, and in this case, it was a mistake. I'm sorry."

Kim made the comment in reference to her Pamela Anderson-inspired outfit, bemoaning the fact that people were too young to recognise her attire.

In a now-deleted video posted on social media, Kim was heard turning to Stephanie Shepherd - her former assistant - and saying: "Nobody knows who I am. Yeah! Retarded."

Kim's apology comes after facing backlash on social media. One user wrote: "So people that don’t know who you are for Halloween are retarded really!! Smh maybe you should spend time with people with disabilities that way you  can show more empathy towards those that are special needs (sic)"

While another told the reality TV start she needs to "do better".