The shot-stopper has been brought in as cover should David De Gea complete a transfer away to Real Madrid this summer as the speculation about his future continues.
Romero has joined up with his new Red Devils team-mates on their pre-season tour and was all smiles as he posed for pictures with manager Louis van Gaal after completing his transfer.
The goalkeeper becomes United’s fifth signing of the summer, following the arrivals of Bastian Schweinsteiger, Morgan Schneiderlin, Matteo Darmian and Memphis Depay.
Romero has penned a three-year deal, with the option to extend for another year.
Asked about why he opted to sign the goalkeeper, Red Devils boss Van Gaal insisted that he had no choice but to bring in reinforcements in goal.
Van Gaal told MUTV: “I know him very well and I think in our situation, if De Gea is going or not going, it is always a threat and we have to take care, make sure that we are prepared and that is why I think it is very good that Sergio Romero is now a Manchester United player.”
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