With reports that a work permit application had delayed finalisation, the club can now at last reveal that Fred has signed a five-year contract that will keep him at Old Trafford until 2023. There is also an option to extend the deal by a further 12 months.
"This is the biggest club in the world and I am delighted to be a part of this amazing team. To work with Jose Mourinho, who has won so many trophies in his time as a coach, is an opportunity not to be missed," Fred told ManUtd.com.
"I cannot wait to get started and to meet my new team-mates. I would like to thank everyone at Shakhtar Donetsk for everything they have done for me over the past five years.
"This is a very exciting time for me with my focus now fully on the World Cup with Brazil."
What shirt might Fred be given at #MUFC next season?— Jamie Spencer (@jamiespencer155) June 5, 2018
10, 13, 16, 22 and 26 all available.
6 might also be an option should Pogba change to 10 as he did at Juventus.#ManchesterIsFred #FredTheRed #FredIsRed pic.twitter.com/vjCsTizXyx
Mourinho added, "Fred will complement our other midfielders' qualities, which we need; his creative brain and passing vision will give us another dimension to our game. I am very happy he is joining our club and I believe our players know how important he can be in our team."
The 25-year-old underwent a medical and agreed personal terms during a brief visit to England with the Brazil national team earlier this month ahead of travelling to Russia for the World Cup.
Fred spent five seasons at Shakhtar after making the switch from Brazilian side Internacional and won 10 trophies with the dominant Ukrainian force.
Set to form an intimidating central midfielder partnership with Nemanja Matic, it is hoped that his arrival at United will benefit Paul Pogba in 2018/19 by releasing the Frenchman to exert more control over games further up the pitch.
Fred is the second signing of the summer for United following the recent arrival of Portuguese teenager Diogo Dalot from Porto. Meanwhile, the club is still actively chasing a centre-back and have been heavily linked with Toby Alderweireld and Jerome Boateng.