"She wasn't sure what she should do," he said. "I advised her not to say anything, because I believed Trump would deny it and try to destroy her."
His comments echo the ones he made on Twitter one day after Stoynoff's account was published.
Stoynoff claimed she bumped into Melania Trump in New York City months after the encounter and said the GOP nominee's wife gave her a hug. Speaking with CNN's Anderson Cooper on Monday, Melania Trump denied being on friendly terms with Stoynoff.
"She wrote … that she saw me on 5th Avenue, and I said to her, 'Natasha, how come we don't see you anymore?'" Melania Trump said. "I was never friends with her, I would not recognize her."
However, friend Liza Herz told People that she was with Stoynoff when the writer bumped into Melania Trump.
"They chatted in a friendly way," she said. "And what struck me most was that Melania was carrying a child and wearing heels."
In a story published Oct. 12, Stoynoff described how Trump got her into a room by herself before forcibly kissing her.
"We walked into that room alone, and Trump shut the door behind us," she wrote. "I turned around, and within seconds he was pushing me against the wall and forcing his tongue down my throat."
At a campaign rally one day after Stoynoff's story was published, Trump denied her allegations and questioned her timing.
"I was one of the biggest stars on television, on 'The Apprentice,' and it would have been one of the biggest stories of the year," he said. "You take a look, look at her, look at her words – you tell me what you think. I don't think so."
>> Related: Trump slams groping allegations as false, politically motivated
His denial came just days after he was heard talking in a vulgar manner about women in a leaked 2005 "Access Hollywood" video.
The conversation, between Trump and "Access Hollywood" host Billy Bush, was caught on a hot microphone. During it, Trump bragged about using his celebrity status to touch women without their consent.
Trump has characterized the comments as no more than "locker room banter."