Kim Kardashian West has been wearing Kylie Cosmetics Lip Kits ''forever''.

The 36-year-old American television personality has teamed up with her youngest half-sister Kylie Jenner, 19, on a four-piece make-up capsule, and the raven-haired beauty has revealed she has been adorning her siblings' products long before she launched her beauty empire and released her debut collection last year, which the teen entrepreneur has continued to expand on.

Speaking in a clip about her latest venture, which has been shared on the Kylie Cosmetics Instagram account, the 'Keeping Up With the Kardashians' star - who has three-year-old daughter North and 16-month-old son Saint with her rapper husband Kanye West - said: ''I have been wearing her Lip Kit forever, since she's been sampling them years ago.''

The 'Selfish' author has been desperate to join forces with the beauty mogul for ''so long''.

She continued: ''But I think Kylie and I have been wanting to collab and do this for so long and I'm so excited. ''

And Kim is ''so excited'' to unveil her make-up line on April 25, as all of the lipsticks are in her ''colour tones''.

She explained: ''So I am just so excited to be doing a collab and doing it all in my colour tones.''

Kim also opened up about her relationship with Kylie, and has likened their bond as ''twin souls''.

She said: ''Kylie and I, our personalities, we are kind of like twin souls. It's like me, my mum and Kylie, like the three of us are all united and we get it. We are different. I don't want to say we are a different breed, but we are so much alike, which can be a good thing, or a bad thing.''