Asked if Ronaldo's comments about his club Manchester United had had an impact on his team as they prepare for the World Cup, Santos said what happened with his highest-profile player has nothing to do with the national squad.
"The player decided to give an interview as many others have," Santos told a news conference on Wednesday in Lisbon.
"It's a personal interview, very personal actually, and we have to respect that.
"Isn't Cristiano Ronaldo a free man?... It was his decision and we have to understand and respect it."
Santos said he had not heard any players mentioning the interview since they reported for duty on Monday.
"The only thing we talk about is the preparation for Qatar. It (the interview) does not affect us at all," Santos said.
He added that Ronaldo was recovering from a stomach problem and would miss Wednesday's practice session and Thursday's friendly with Nigeria.
"He is in his room resting and recovering. He won't practice and won't be ready for tomorrow's game either," coach Santos said.
Benfica's 19-year-old defender Antonio Silva could be in the starting team against Nigeria ahead of Manchester City's Ruben Dias.
"He will play but I'm still deciding if it will be from the start," Santos said.
"I have full confidence in the group. Not only Ronaldo but all the players are very focused.
"The players have given me absolute guarantee - not that I need it - of the total focus and ambition they have for this World Cup."
Portugal are in World Cup Group H with Ghana, Uruguay and South Korea.
