Ronaldo, who rejoined United from Juventus for a second spell at Old Trafford in 2021 on a two-year deal, said in an interview with Piers Morgan for TalkTV aired on Sunday that he had no respect for manager Erik ten Hag.
"Manchester United notes the media coverage regarding an interview by Cristiano Ronaldo. The club will consider its response after the full facts have been established," United said in a statement on Monday.
"Our focus remains on preparing for the second half of the season and continuing the momentum, belief and togetherness being built among the players, manager, staff, and fans."
Ten Hag said last month that the Portuguese refused to come on as a substitute against Tottenham Hotspur when the Portugal player walked down the tunnel with a few minutes of the match remaining after being left on the bench.
The five-times Ballon D'Or winner was not part of the squad that faced Chelsea the following Saturday and missed United's 2-1 win over Fulham on Sunday due to illness.
United are fifth in the league table on 26 points from 14 games with the season pausing for the November 20-December 18 World Cup in Qatar. Ronaldo will captain Portugal in the tournament.
