Messi and his legal team believe that the player unilaterally rescinded his Barca contract last week, and the 33-year-old has since refused to attend training sessions with new coach Ronald Koeman.
Barca say that the relevant clause expired in June, Messi's contract remains valid and the only way to change that is by paying his €700 million buyout clause.
"I think [Messi] has earned the respect to decide his future," Ramos said in a news conference ahead of Spain's UEFA Nations League game with Germany on Thursday (watch live on ESPN2, 2:45 p.m. ET). "I don't know if he's doing it in the best way. But of course, for Spanish football, for Barcelona and for us, we always like to win being the best. We would like him to stay here."
Jorge Messi -- the player's father and agent -- arrived in Barcelona on Wednesday for talks with Barca president Josep Maria Bartomeu aimed at ending the stalemate over his son's attempt to quit the club.
If the deadlock can be broken, Manchester City are favourites to sign the six-time Ballon d'Or winner, in what would be a major blow for La Liga.
"Leo makes the Spanish league better, he makes his team better and he makes the Clasico more attractive. We like to win with the best there and he's one of the best in the world," Ramos said. "There isn't much to add, he's won the respect to decide his future, him alone, without any speculation at all. Let's see what happens."
Messi is the all-time Clasico top scorer, with 26 goals in the fixture since 2007.
ESPN has reported that Real Madrid's players were "incredulous" when reports first emerged of his desire to leave, as midfielder Toni Kroos admitted on Wednesday on the podcast he hosts with brother Felix.
"The news surprised me," Kroos said. "Messi is one of the best of all time. If a player of that calibre stops playing for your biggest rival, you wouldn't exactly be too upset."
Kroos admitted that Manchester is the most likely destination for Messi -- saying "I don't have any inside information. I think the most likely would be Pep and City" -- and doesn't think a shock switch to the Bernabeu is on the cards.