Nasri has enjoyed a superb season for the English champions but will not play in Brazil this summer after controversially being left out by national coach Didier Deschamps.
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.
Vieira, 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 the 26-year-old, 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."
Nasri scored 11 times for the City during the season, including a crucial goal in the Capital One Cup final win over Sunderland in March.
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 Barclays Premier League 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."
City had hoped to visit Abu Dhabi, homeland of their owner Sheikh Mansour, in January but postponed the visit due to an FA Cup third-round replay.
Captain Vincent Kompany, who will also have a crucial role to play for Belgium in the World Cup, suggested he was unlikely to be involved.
Kompany said: "We have the World Cup to come, the main thing for us is to come here and celebrate the link between City and the UAE and that's our mission today.
"The game tomorrow, if we can play, then good, but if not, we've had some great experiences here so far."
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.
"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."