Vettel drove for the Faenza-based team when it was known as Toro Rosso before moving to Red Bull and winning four world championships prior to leaving for Ferrari.
He remains on friendly terms with the Milton Keynes-based team and its boss Christian Horner.
Speaking in an ITV interview at Goodwood on Saturday, Vettel stressed that he is happy to see his former team-mate Daniel Ricciardo make a return to the grid, but said that the turn of events was unfortunate for De Vries.
When asked for his thoughts on the AlphaTauri news, Vettel said: “Twofold if I'm honest.
“I'm very happy for Daniel, very happy. I like him, obviously, I raced with him, and I met him at the test when I was shaking down the [1993] McLaren for this weekend. And I'm very, very happy for him.
“On the other hand, you have to be honest as well. It's obviously a shame for Nyck, the way it comes to an end. I think he was given a great chance.
"Maybe things didn't happen for him the way he expected, or people expected. But it's also a bit harsh when it comes to a very sudden stop like that. It's brutal.”
Source: Autosport