"I'm just and tired of him playing with me," Chyna says in the clip

Tensions are high on this week’s Rob & Chyna and it’s all over … french fries?

In a sneak peek at Sunday’s episode, Rob Kardashian and his fiancée Blac Chyna end up in a screaming match in the car after some of Kardashian’s food accidentally falls to the floor.

Kardashian, who is driving, turns to Chyna, who sitting in the passenger seat with her phone in one hand.

“You’ve got to choose one: the food or your phone,” he says in the clip released by E! News. “What’s more important?”

“These are my fries. Those are your fries,” says Chyna, 28.

“Yeah, I know. I’m saying you’ve got to choose one — are you not going to help out?” demands Kardashian, 29.

“I’m about to — didn’t you just see I’m about to go down?” she replies. “I didn’t see that s— falling. God, you’ve got to relax.”

Kardashian maintains he hasn’t raised his voice, but Chyna snaps back that he should have been holding his own food.

“He’s going to tell me I have to choose between my phone and holding his food?” Chyna tells the camera. “I’m not your mother! Like, you better hold your own food or put it between your lap. He’s going to get mad at me over some french fries and start yelling at me? Like, what?”

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Kardashian, meanwhile, chuckles to himself and says: “Yo, you have serious anger issues.”

“How am I going to grab your fries that’s falling?” she yells.

“Why are you yelling, you psycho?” he asks. “What’s wrong with you?”

“‘Cause it’s aggravating!” she snaps.

“Take the tongue ring out and relax,” he replies.

“No, mind your business and relax,” she fires back.

“Rob likes to pick with me, he loves to see me get hot,” says Chyna. “And I’m just and tired of him playing with me.”

Rob & Chyna airs Sundays (9 p.m. ET) on E!