"I know for sure he was at Van Gaal's house, the chairman," said the former Netherlands great.
"I think it's a done deal but you never know," added Gullit who had a spell in charge of Tottenham's London rivals Chelsea from 1996-98.
The BBC said an unnamed Spurs source had questioned the timing of any meeting between Van Gaal and Levy, suggesting it could have been before Tim Sherwood was appointed in December.
Former Ajax Amsterdam, Barcelona and Bayern Munich coach Van Gaal is standing down as Netherlands coach after the World Cup in Brazil ends in July.
He has indicated his interest in managing in the Premier League, saying last month that his next challenge should be a club in England.
"Maybe Tottenham are coming but, first, we have to go to Brazil," the 62-year-old said then.
Spurs also approached Ajax coach Frank de Boer before appointing the inexperienced Sherwood as manager on an 18-month contract when they sacked Andre Villas-Boas.
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