The Netherlands great told the Ajax defender, one of the most sought after in Europe, not to join the Red Devils due to a lack of Champions League football.
Ajax star Matthijs de Ligt should avoid joining Manchester United this close season, according to Ruud Gullit.
No Champions League football
De Ligt, 19, has been linked with numerous European heavyweights, including United, Liverpool and Barcelona, although Paris Saint-Germain are reportedly favourites to sign the centre-back. Netherlands great Gullit feels his fellow Dutchman should not head to Old Trafford after United missed out on Champions League qualification.
"I hope he makes the right decision"
"I don't think Man United, they don't play [in the] Champions League," he said, speaking at the Costa Smeralda Invitational.
"I think he wants to play Champions League. So, that's unfortunate for Man United.
"It's going to be difficult, a lot of them maybe have a UEFA ban, so there's a lot that's going on still. So I hope he makes the right decision for himself."
De Ligt captained Ajax to a domestic double last season, while they also reached the Champions League semi-finals.