Manchester United s Dutch manager Erik ten Hag (R) watches as Manchester United s Portuguese striker Cristiano Ronaldo (C) . AFP
The five-time Ballon d'Or winner said he did not respect United manager Erik ten Hag and took aim at the club's owners, the Glazer family, during the 90-minute interview aired on TalkTV.
"Manchester United has this morning initiated appropriate steps in response to Cristiano Ronaldo's recent media interview," the club said in a statement.
"We will not be making further comment until this process reaches its conclusion."
Ronaldo was suspended by the club for a 1-1 draw at Chelsea after refusing to come on as a substitute against Tottenham last month.
The 37-year-old claimed during the interview with Piers Morgan that he felt "provoked" into that reaction by Ten Hag.
"I think he did it on purpose," said Ronaldo. "I felt provoked. I don't have respect for him because he doesn't show respect for me."
Ronaldo has been a peripheral figure on the field during the Dutchman's first season in charge at United, scoring just once in the Premier League.
But he did return to the team and even captained United in his last appearance for the club in a 3-1 defeat at Aston Villa.
Former United captain Gary Neville said on Thursday that the Red Devils have no option but to rescind Ronaldo's contract, which runs until the end of the season.
Ronaldo is currently preparing to play in his fifth World Cup with Portugal in Qatar.
He revealed he hopes to keep playing until he is 40 and dismissed reports of a lack of options should he move clubs in the January transfer window.
The Portuguese won three Premier League titles and the Champions League during his first stint at Old Trafford between 2003 and 2009.
But his homecoming, when he rejoined the club from Juventus in August 2021, has turned sour.
United failed to qualify for the Champions League after finishing sixth in the Premier League last season, despite Ronaldo's 24 goals in all competitions.
After a disastrous start in defeats to Brighton and Brentford, Ten Hag is beginning to turn things around for the English giants, but the majority of United's best performances this season have been when Ronaldo has been left out.
United have won only once in the league all season when Ronaldo has started, but the team remain in the hunt for a return to the Champions League.
Ten Hag's men sit fifth in the Premier League table, three points behind Tottenham with a game in hand.
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