The French midfielder has enjoyed an eye-catching season in the Premier League at the London club to fuel talk of a lucrative summer move for the 25-year-old.
Doucoure fanned the speculation earlier this week when he spoke about his “dream move” to Liverpool FC ahead of the summer transfer window.
Arsenal have also ben heavily linked with a move to sign the dominant midfielder to improve their options in the middle of the park.
Doucoure has scored seven times and has made two assists in 30 appearances in the Premier League this season.
However, Watford boss Garcia wants his star player to remain at the London side.
“Doucoure is playing for a very big team, and playing in the Premier League, and in the future I would like him to play with Watford in Europe,” Gracia said, as quoted by the Daily Mail.
“Maybe in the future he can play with other big clubs who play in the Champions League.
“But what I feel at this moment is that all of our players are proud to belong at this club. They are concentrated on the next match and trying to put the team as high in the table as possible.”
The Watford star moved to Vicarage Road from Rennes for an undisclosed fee in the 2015 January transfer window.
Doucoure spent the remainder of the 2015-16 season on loan at La Liga outfit Granada CF before linking up with his new Watford team-mates ahead of the 2016-17 campaign.
Liverpool FC are facing uncertainty surrounding their German midfielder Emre Can ahead of the 2018 summer transfer window.
The Reds finished in fourth place in the Premier League last term to secure a return to the Champions League after a two-season absence.
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