With the World Cup looming, the Euro 2016 champions are gearing up for their first group stage game, a mouthwatering tie on Friday against Spain, regarded as one of the favourites to win the competition.
Silva, who enjoyed a solid first season with Manchester City, believes that Portugal have a squad deep enough to maintain their current level, but he accepts that they will not be able to merely replace Ronaldo, who has developed into a phenomenon since winning his first cap in 2003.
"It's important that people understand that he's irreplaceable," Silva said, per Marca .
"When he wants to leave, there will be a group with a very high level and I think we can maintain that.
"I hope to be one of those players, I have ambition and obviously I will give my best to help.
"When Cristiano goes, we will lose the best player in Portuguese football.
"We will try to keep this level with the national team, but it doesn't worry me right now seeing myself in the role of the fan's idol.
"These things can happen or not, but they have to be natural."
While talk of Ronaldo's exit from the international stage may well prove premature, Silva insists that he and his team-mates are all trying to follow the example set by the former Manchester United attacker, who is refusing to rest on his laurels.
"Ambition is [Ronaldo]'s strong point," he added.
"He's a player that has five Ballons d'Or and five Champions Leagues, who has spent 10 years scoring more than 40 goals a season... All together it's tremendous.
"That he's managed to maintain that level gives you an idea of what he represents as a player. The majority with two or three Ballons d'Or want to relax and enjoy the easy life, he keeps pushing for a higher level.
"He's our reference point, an example for everyone and we hope that he's in his best form because only if he's good can Portugal hope to achieve big things."