The tension that had built up between siblings on Keeping Up With The Kardashians in Season 17 suddenly broke out into a fight in the Season 18 premiere on March 27.

Kourtney Kardashian and her sister Kim Kardashian came to blows and used foul language on each other.

The latest teaser trailer to the longest running reality TV show revealed what was going on.  The fight began when Kim commented on Kendall Jenner’s and Kourtney’s work ethic, saying that her sibling did not care about stuff. Kourtney replied that Kim was acting like she did not do anything. Kourtney continued directing foul language at Kim and then threw  a drink at her.

Kourtney Kardashian and her sister Kim were in a fight. Picture: Instagram

Kim then responded by slapping her sister.

On The Tonight Show With Jimmy Fallon, Kim shared why did the fight began. She revealed that there was a lot of tension with her sister.

Kim said she hit Kourtney because she had been scratched so hard that she was bleeding. The detail cannot be seen on camera but Kim said Kourtney had clawed her on her arm and that she also felt it on her back.

The aftermath is that Kourtney has apparently left the show and she made the announcement on Twitter on March 27.

A netizen had commented that Kourtney should leave the show. She replied that she had done that. /TISG