The Colombia international, who was attracting interest from Arsenal and Manchester City over the past week, is expected to complete an £11m loan move to the 20-time English champions.
The 28-year-old striker scored 11 goals in 20 Ligue 1 appearances following a big-money move to cash-rich Monaco from La Liga holders Atletico Madrid last summer.
And former United forward Ronaldo backed the Red Devils’s pursuit of the prolific finisher.
“He is very good player. I think Manchester did very well. I don’t think he is the wrong type of player. He is a top player so I don’t think it is a wrong buy,” Ronaldo said.
“I think he will be a fantastic buy. Manchester have not started well, two points, so they need quality players and Falcao is a quality player.”
Falcao has won the Europa League with Atletico and Porto but hasn’t played in the Champions League since 2010.
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