The Tottenham midfielder has been in sparkling form this term and is one of the key reasons behind Mauricio Pochettino's men's charge to within seven points of Chelsea at the top of the table.
On Tuesday Pochettino refused to give any guarantees that the 21-year-old, who was this week named the PFA Young Player of the Year for a second consecutive year, would definitely be at White Hart Lane.
But while admitting he is a huge admirer of the England man Guardiola says he won't be pursuing in the summer window.
“Mauricio Pochettino has to stay calm,” he said. “Dele Alli will be his player next season. I am pretty sure about that.
“We don’t want him. He is a fantastic player, good, new, English footballer.
"He’s a fighter. He’s good. He’s someone who attacks the box and is one of the most fantastic players I have ever seen in my life.
“But Manchester City doesn’t want Dele Alli.”
City face rivals United on Thursday evening with a spot in the top four potentially on the line at the Etihad.
And Guardiola confirmed that his team may be without David Silva although could welcome back Gabriel Jesus into the starting line-up.
"David Silva is a real, real doubt, I don't know if he will be ready to play after what happened in the first minutes in the semi-final of the FA Cup.
"Gabriel has no pain at all, so is ready but has had three months out, so his physical condition is not optimal.
"Sergio is much better. Today he makes a short part of the training session, tomorrow we will wait (and see)."