The Colombia international joined the Red Devils on a season-long loan deal from the Ligue 1 club last summer but has struggled to find consistent form for the Premier League outfit.
Falcao was widely regarded as one of Europe’s top strikers before his move to Old Trafford.
However, the 29-year-old forward has only managed to score four goals in 16 Premier League games for Louis van Gaal’s side so far this season.
Monaco chief Vasilyev insists that he still has faith in the forward and believes that he just needs some help to get through his difficult spell.
Vasilyev told NBC Sports: “I am not worried for Falcao. He is a great player and goal-scorer.
“Mentally he is strong and technically he is one of the best.
“Sometimes you have a difficult spell, and little things make the difference. It can be the trust of the coach.”
Falcao’s most recent appearance for Manchester United was during the 3-1 FA Cup win over Preston North End earlier this month, when he was substituted on the hour-mark.
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