United are set to finish second in the Premier League for the first time since 2018, and are on the brink of reaching the Europa League final after a 6-2 win against Roma in the semifinal first leg on Thursday.
Speaking ahead of Liverpool's visit to Old Trafford on Sunday, Klopp praised the Norwegian for turning United into challengers once again.
"It's nice to see when the quality of a manager is more important than the experience you have," Klopp said.
"If you need to have 50 Champions League games as a manager before taking on a club like Manchester United, it'll be tricky to find one because there are not a lot of coaches out there with that experience.
"I think it's clear if Ole wouldn't have had successful history at Man United as a player then probably not so many people at United would've thought about him. But, because he did a brilliant job in Molde and has a Manchester history, that was the idea and nobody knew how it would work.
"It worked absolutely sensationally from the beginning and then had a little dip and now they look really good and he deserves credit for that together with his coaches. I'm happy for him to be honest because I'm really happy for a colleague to do really well and that's what he does."
A Liverpool win at United will see Manchester City crowned Premier League champions for the third time in four years.
Liverpool also face an uphill task in securing Champions League qualification next season as they find themselves seven points behind fourth-placed Chelsea.
"I don't want to hold him back but you cannot force it as well," he added. "If you want to play at a tournament, you have to have proper football training before. You cannot have 10 or 11 months out and train a week and play football, that's just not possible.
"Noboby is holding him back, I can promise all the people in Holland but we cannot force it. We're speaking about a player and his career so nobody should force it and nobody will -- not Holland, not us and not Virgil.
"He just tries to get fit as quickly as possible but nobody knows when that will be exactly. You can imagine that it will be very tight for the Euros because he's not in team training yet and will not be in the next weeks. In the end, it's Virgil's decision and he will be influenced by the feeling in his knee."