'You are a slut and a liar!' Bethenny Frankel calls out Luann de Lesseps as Christmas party descends into catty chaos on RHONY

Bethenny Frankel faced off against Luann de Lesseps on Wednesday on The Real Housewives Of New York City as Dorinda Medley's Christmas party descended into catty chaos.

Bethenny blasted her reality TV rival and accused her of sleeping around and partying too hard during an explosive row at Dorinda's house.

The furious entrepreneur told Luann: 'You just pretend you're something you're not. I've told you this before Luann. You're not a girls' girl.'

Christmas chaos: Bethenny Frankel ranted against Luann de Lesseps during a Christmas party on Wednesday's episode of The Real Housewives Of New York City

When Luann accused Bethenny of not being a 'girls' girl' either, Bethenny was swift and brutal with her retort.

'What married man have I ever slept with? What young 25-year-old have I f***ed and then given my friend s*** about it. You are a hypocrite. You f*** everyone and you pretend you don't.

'I'm calling you out on your bulls*** because no one besides me has the balls to do it. You are a slut and a liar and a hypocrite and a snake. That's the truth.'

Bethenny and Luann's argument erupted after Bethenny thought Luann was trying to take credit for her Skinnygirl cocktail brand.

Called out: Luann found herself on the defensive as Bethenny lashed out at her

'It was my idea that I told you about and that you then told everybody else you'd thought of,' Bethenny said.

'We weren't together when it came up sweetie pie.'

Bethenny took it down a notch and tried to vent just to Ramona Singer. 

Going off: Bethenny first warmed up chiding Luann for taking credit for her lucrative Skinnygirl brand

Whispering about her fury to Ramona, she said: 'I'm like 'you wanna f***ing go? I'll take you by the neck outside. I'll f***ing smack her with a reindeer antler.'

Luann however was just a few feet away and could hear everything so another confrontation erupted. 

Addressing Luann once again, Bethenny shouted: 'You're so full of s***. ''We came up with this idea together''. Don't say you didn't say that. 

'You said it, you said you would take me down. I'm sick of your bulls***,' Bethenny screamed.

Her side: Luann earlier insisted that she was with Bethenny when the brand was born

Host Dorinda told the cameras: 'Bethenny is truly like a sniper. When she puts that red eye on your forehead you're done.'

Luann tried to defend herself against Bethenny's verbal tirade and had a dig at the businesswoman by noting the similarities in their hairstyles.

'We've got the the same hair. What's the deal? It's looking a lot like mine lately,' she quipped.

Same hair: Luann also pointed out that Bethenny copied her hairstyle

Red eye: Dorinda Medley compared Bethenny to a sniper who locks in on her target

Party pad: Dorinda was hosting the sleepover and Christmas party at her estate

'What does that mean?' Bethenny asked. 'So I want to be just like you? I want to understand it. I f*** a lot of different guys, party until five in the morning?'

'Are you getting laid right now or not?' Luann asked.

Bethenny snapped: 'You're making up for all of us, but I'm doing OK.'

Kind of snapped: Bethenny flat out called Luann a slut during her tirade

Great party: Jules Wainstein thought she was going to a fun holiday party with gifts exchanged and joy

She told viewers: 'Saying what I said to Luann made me feel like a constipated person that took a giant s***. I felt some relief but it's embarrassing. I'm at someone else's house and I just called her a whore.'

Bethenny was not the only Housewife to row with Luann. Ramona also told her friend she was less than impressed when she started dating her ex Tom D'Agastino.

Told that Ramona and Tom had been on seven dates, Luann said: 'I don't care. You know why? Because it's before I met him. I couldn't give a s***.'

Felt bad: Bethenny was embarrassed after flipping out and calling Luann a whore

Same guy: Luann talked to Ramona about dating her former fling Tom

Girl code: Ramona invoked the often ignored and murky Girl Code and said Luann should have told her about pursuing Tom

'You went over to him and said 'oh you were seeing Ramona? Well I'm next',' Ramona said, accusingly. 'It's called the girl code.'

Dorinda, meanwhile, lost control when confronted with the shouting matches surrounding her and told her friends they were a 'disgrace'.

'I think everybody is acting very poorly. I put in a lot of effort, this is my home and I made a conscious choice not to invite Sonja so we could all have a good time. I think it's a disgrace of you people,' she yelled.

The hostess: Dorinda got sick of all the fighting and told the women they were acting 'very poorly'

Awkward conversation: Luann vented about Bethenny while Jules was talking to family about her dying father

Close to tears she added: 'I cooked all day, I decorated, I did it nice. I'm ashamed. If no one can behave yourselves then you all go home. I give you permission. All go home.'

While her fellow Housewives were partying and rowing without her, Sonja Morgan decided to pamper herself – with a vaginal lift.

'My girlfriends are up having a fabulous dinner and drinks without me. I may as well resurface my vagina,' she said.

That backfired: Sonja Morgan was not invited to the party in order to keep peace

'The only thing worse that trout mouth is trout snatch. That's definitely not going to be allowed to droop.'

Undergoing a Femilift – laser vaginal tightening – treatment at Lexington Medical, Sonja expressed concern that she was a 'vaginal guinea pig'.

'I can do this,' she reassured herself. 'Anything for a tighter, lighter, brighter vagina.'

Tighter and lighter: The reality star underwent laser vaginal tightening instead of going to the party

 Holding on: Sonja held the hand of a clinic staffer during the procedure

But during the procedure she gasped: 'I'm glad this is a one night stand.'

Back at Dorinda's house, Luann sent text messages to both Carole Radziwill and Bethenny, apologizing for her behaviour.

But Bethenny later caught her complaining about her in the kitchen and the drama looked set to continue next week.

Duly noted: Carole Radziwill while spying on Luann told Jules that closet wallpapering was a sure sign of wealth

So sorry: Luann texted Carole that she was sorry for calling her a pedophile

More drama: Bethenny after getting an apology text from Luann overheard her making snide remarks