Khloe Kardashian and Lamar Odom at launch of their fragrance 'Unbreakable' at Redbury Hotel in Hollywood, California.

Khloe Kardashian and Lamar Odom at launch of their fragrance 'Unbreakable' at Redbury Hotel in Hollywood, California.

Rob Kardashian has branded his sister Kourtney's boyfriend Scott Disick an 'alcoholic'.

In a new clip of an upcoming episode of Keeping Up With The Kardashians, Rob, 24, reveals it is 28-year-old Scott that's the reason why he hasn't visited his and Kourtney's new house yet.

Rob finally gets round to visiting Kourtney's new house five months after they moved in to spend time with nephew Mason, 18 months.

While round there Rob is seen complaining about a stomach problem and Kourtney claims it could be excess drinking.

But Rob is unimpressed and replied: "The reason I don't come over here is because of Scott. He's an alcoholic! He's a negative person in my life. Like, [he] has a kid.

"Show me that you're mature and show me you're mature enough to have a kid with my sister."

Kourtney then said: "I don't need these negative thoughts being said about Mason's dad around him."