The Chilean international has over one year left on his contract and has not yet committed his future to the north London club. His manager Arsene Wenger admitted talks over new deals for the forward and Mesut Ozil — who also has one year left on his deal — will resume after the end of the season.
Sanchez's uncertain future at the Emirates has seen him attract interest from the top clubs across Europe. The Independent reports Atleitco Madrid manager Diego Simeone is interested in the 28-year-old, while the Telegraph claims Bundesliga champions Bayern Munich are preparing a £55m ($70.8m) bid in securing the forward's services.
In addition to this, Chelsea are also believed to be in the race in signing Sanchez. Bolt wants the former Barcelona man to snub advances from Atletico, Bayern and the west London club and join the Red Devils as he believed he would be a great addition to Jose Mourinho's side.
"I know that he plays for Arsenal, he should leave," Bolt told Fox Sports Vivo, as quoted by the Evening Standard.
"He would be great [at United], he's a player I've always said over that years who is great at picking the ball up and creating chances for other people. He's proven himself to be one of the best."
Bolt, who has long been a fan of the 20-time English champions, has expressed his desire to offer his services to United in the future. He said, "There are many things I can do."
"I will definitely be sticking around track and field, my charities I want to work on and I've always said I wanted to try to play football so we will see how that works out. You never know where it will be, but I definitely want to get a chance [at United] to see."
Sanchez has admitted that he will decide his future after the end of the season. Wenger's side have three matches left in the league and will have to fight with Chelsea in the FA Cup final.
Arsenal are currently fifth in the Premier League and are fighting to qualify for the next season's Champions League. Securing a berth in Europe's elite competition will be key for the Gunners to keep the South American forward at the club beyond the summer transfer window.