"Obviously I'm going to see out the rest of the term, and then it's sayonara Nikki [Kaye], sayonara Todd [Muller]."
The clip has a surprise ending with Sainsbury in a grey wig dancing around Bennett's living room with the real Paula Bennett - both in colourful kimonos.
Bennett said today she had no idea what the comedian would say in his video. He filmed the impersonation at his home.
"I had no idea what Tom was going to do and has comedian license, which I suppose is a way to do it," Bennett said.
"I'm hardly ever going to tell Tom what he can and can't do. He's been doing a parody for years - some of which I've found funny, some of which I've winced at and most of which I'd never say so why would someone take that seriously."
Asked whether she'd endorse the "eff you" message in hindsight, Bennett said: "Of course not."
Bennett also said for the first time today National leader Todd Muller did know she was leaving before Sainsbury.
She just hadn't told Muller when she'd make the announcement but gave Sainsbury the head's up.
"To be fair I didn't decide that until the Sunday and Todd wouldn't look good in a kimono."
Muller said this morning Bennett's appearance didn't bother him.
"According to my daughter there are all sorts of TikTok videos around of me that are even worse so I'll just have to run with it."