In the clip, Kim, 42, can be heard on the phone telling her older sister: “Are you happy? You’re a different person, you hate us … We’re all just talking about it.
“You think things, so you get riled up. I think things, so I’m getting riled up.”
Kourtney, 44, is then shown responding, holding back tears: “You’re just a witch and I hate you.”
In another clip, Kourtney is shown sitting next to her sister. A producer asks if he thinks viewers will be surprised to see them together, to which Kourtney responds: “Last season was really hard.”
The trailer suggests that more family drama is to follow in the popular reality TV show.
The third season of The Kardashians featured on a growing rift between Kourtney and Kim, much of which revolved around comparisons between their respective weddings.
Kourtney married Blink-182 drummer Travis Barker in May of 2022 in Portofino, Italy. Their wedding was curated by the Italian designer duo Domenico Dolce and Stefano Gabbana.
Shortly after the wedding, Kim was offered the opportunity to be the creative director for the Dolce and Gabbana Spring 2023 collection, a partnership that she allegedly accepted without speaking to her sister first.
“She chose the money over me,” Kourtney alleged at the time in an episode from that season.
Meanwhile, Kim explained the initial collaboration was meant to be between Skims and the Italian fashion house. But when she realised they couldn’t make that happen, she called Kourtney to let her know.
“Then I called you. I said: ‘Skims is not doing it,’ because we couldn’t get it together that quickly. I kept saying: ‘I don’t want to do this because it’s so close to Kourtney’s wedding – I want it to be completely different,’” she claimed.
However, Kourtney protested that the situation still hadn’t been handled properly.
“You weren’t like: ‘Hey, I’d love to know how you feel about this.’ You called me after the deal was done,” Kourtney told her.
The rift deepened when Kim proceeded to point out the similarities between her sister’s wedding and her own.
“I got married in Italy. Am I saying you copied me by getting married in Italy?” Kim said. “Who performed at my wedding? Andrea Bocelli. Who performed at Kourtney’s wedding? Andrea Bocelli.
“Andrea Bocelli is my favourite male singer of all time, but I’m copying her dolce vida lifestyle? Okay.”
Season four of The Kardashians will launch on Hulu and Disney+ on Thursday 28 September.