Nasri enjoyed a superb finish to the season, including goals in the Capital One Cup final against Sunderland and the final-day win over West Ham which made sure of the Barclays Premier League title.
And the 26-year-old, who was also left out of the 2010 World Cup by then-coach Raymond Domenech, told Sky Sports News: "It's a little bit hard to accept.
"I need to take some time now to think about the national team because it's been twice now that they take away a World Cup from me.
"You can go around and ask any player if they're happy to be on the bench, nobody's going to say yes.
"I need to think a little bit during the holiday, what will be my future in the national team, because missing two World Cups is really hard for a player."
While Nasri's absence was greeted with widespread surprise, the player himself said: "I must confess, I knew before.
"Sometimes you have the feeling, when you call to speak to the manager and he doesn't want to speak to you, you know you're not going to go to the World Cup.
"It was a shock, but I was prepared mentally. I'm okay.
"I respect his choice. He wanted to not pick me... good on him. I wish good luck to the French national team."
Former France captain Patrick Vieira has expressed his surprise at Nasri's exclusion.
Vieira, a member of France's 1998 World Cup-winning squad when Deschamps was captain, has seen at first hand much of Nasri's fine campaign.
The former Arsenal captain is now the coach of the elite development squad at City.
Vieira tweeted: "It is a surprise not to see @SamNasri19 on the way to Brazil. For me, the way he played his year would have put him on the plane."
Deschamps defended his decision to omit Nasri, suggesting the former Arsenal star was not an ideal squad player.
Deschamps told reporters: "Samir is an important player for Manchester City but he has not performed that well with France.
"He is a starter at City, which is not the case with France, and he has made it clear that he is not happy when he is a substitute - and I can tell you it can be felt in the squad."
City manager Manuel Pellegrini was asked about the matter at a press conference in Abu Dhabi ahead of his side's post-season friendly against Al Ain.
Pellegrini said: "I was talking with all of the players, with Samir of course, it's not good news for him.
"He's a very good player and deserves to be in the national squad but all teams have managers and it's up to them to decide."
Nasri's exclusion might make it more likely that he plays against Al Ain in City's first match since securing the title on Sunday.
Pellegrini had previously said that players involved in the World Cup would not feature.
The trip has caused some consternation, with England manager Roy Hodgson expressing reservations about its timing so close to the beginning of his final preparations for Brazil.
Asked about the issue again, Pellegrini said: "All of the players who are going to the World Cup - we'll see if they play tomorrow.
"It is a risk. We are very happy to come here with the whole squad.
"Tomorrow I will ask all of them if they want to but it will be difficult for them to play."
Pellegrini will soon turn his attention to next season and one of his prime objectives will be to make further progress in the Champions League.
City qualified for the last-16 stage for the first time this season after two previous failures to get out of their group.
Pellegrini said: "I think that during next week we are celebrating here in Abu Dhabi what we did last season. It was very important to win the league.
"Next week we will start working on how we can improve.
"It's important to improve every year on what we did in the last season.
"We also want to have a better performance in the Champions League.
"To win the Champions League you have to fight with very important teams.
"This year we were very unlucky because we played with one player less against Barcelona (after Pablo Zabaleta was sent off).
"I don't know if we are going to win it next year but we will try to get at least one stage further. We must improve in all senses."
- Sports & Recreation
- Didier Deschamps
- Manchester City