The full-back has signed for the Red Devils on a season-long loan, coming in to provide cover for the injured Luke Shaw and Tyrell Malacia at left back.
Erik ten Hag confirmed in his press conference on Friday that the 26-year-old will be available to play against Arsenal - his parent club's rivals - at the Emirates this weekend.
Speaking about his move to Old Trafford, Reguilon told said: "In life you have to be ready for everything and the chance to represent this great club with such an illustrious history is one that I could not turn down.
"Having spoken to the manager, I know what he needs from me, and I am ready to play my part in helping the team to achieve success.
"I know that I can contribute to Manchester United this season; I am ready to fight for this group and show everyone my qualities."
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