Guardiola’s Manchester City hold a 15-point lead over Mourinho’s Manchester United, who are their nearest challengers after 25 games.
Mourinho said at a news conference on Friday that United “have to try to finish second” but Guardiola immediately responded by saying all was still to play for.
Speaking at his own press conference to preview Saturday’s trip to Burnley, Guardiola said: “There are 13 games, 39 points to play (for).
“We have (a lead of) 15. It’s not over.
“We have amazing, tough games to play, for example tomorrow. We cannot deny how complicated it is playing at Burnley.
“After that we have to go to Stoke City, Goodison Park, we have games against Arsenal, Tottenham, United, Chelsea. Definitely it’s not over.”
City have already beaten Burnley twice at the Etihad Stadium this season - 3-0 in the league and 4-1 in the FA Cup - but neither were as straightforward as the final scorelines suggest.
The Clarets are enjoying an outstanding campaign and will go into the game seventh in the table.
Guardiola said: “Last season we won there but it was one of the toughest games we played. It will be tough.
“We have to avoid fouls, we have to control the second balls and long balls to (Ashley) Barnes in the box.
“They are masters, they are one of the best in the Premier League in this style. In this system they create a lot of pressure.
“In free-kicks and corners they are so good. We have to avoid it this kind of game as much as possible and do our game to make another step to the title race.”
Playmaker David Silva is doubtful for the game after leaving the field with a side injury in the midweek victory over West Brom.
“On Thursday he could not train,” Guardiola said. “He was recovering. He had a painful kick in the side. We are going to see today how he feels.”
Guardiola delivered a positive update on long-term knee injury victim Benjamin Mendy, saying he was on course to return to training some time in March.
Striker Gabriel Jesus still requires “four or five weeks of rest” after a knee injury.
A number of City players have been on the receiving end of some bad tackles in recent weeks, prompting Guardiola to call for for better protection from referees, but he did not want to discuss that matter further.
He said: “I’ve said enough. I think we were clear. Playing football again — tomorrow at 1230 — that’s what I’m thinking about.”
Meanwhile Burnley’s Belgian midfielder Steven Defour is expected to miss the rest of the season — and the World Cup — through a knee cartilage injury, manager Sean Dyche has said.
Dyche said: “It is likely to be the season, I would think.
“He wanted to carry on with it. He had a sore knee but nothing major, and he was getting on and managing it wisely over the last few weeks.
“It was only really a precautionary scan that showed there was some cartilage off his knee and he’s going to have to have that dealt with.
“Depending on what they do, it could be the season, and there’s a strong chance it will be the season.”
Premier League: Burnley v Manchester City
Turf Moor, 12:30
Sky Sports PL
Burnley 10/1, Man City 1/4, Draw 9/2