Spurs produced a clinical display to see off Manchester City 2-0 on Saturday (November 21) thanks to a goal in each half from Son Heung-min and substitute Giovani Lo Celso.
They have won four games in a row in the top flight, are seven without defeat and will finish a day at the summit of the league for the first time since August 2014.
Premier League: Tottenham 2-0 Manchester City: Spurs go top as Mourinho beats Guardiola again
But Mourinho, who celebrated one year in charge on Friday, does not believe his side can realistically compete for the title.
“It feels good [to be top], but maybe tomorrow we are second again and honestly that would not be a problem for me, I am just happy with the evolution,” he told BBC Sport.
“People cannot expect us to come here and after one season we are fighting for the title.
“We are not fighting for the title, we are just fighting to win every match. But we are going to lose matches, we are going to draw matches.
“Dinner tonight will be nice and relaxed. I will watch Atletico Madrid v Barcelona and sleep like an angel. But no problem if Leicester win [tomorrow] and we are second again.”
Tottenham scored from their only two shots on target – compared to five such attempts from City – in a game that saw them have 34 per cent of the ball.
Mourinho’s men were well drilled and the Portuguese praised his players for sticking to the plan as he got one over on long-time rival Pep Guardiola.
“That discipline is not just about a plan, it’s about an emergency plan. In case somebody makes a mistake you have to ready for it,” he said.
“That discipline requires a great effort. I’m so proud of all of the players. They were fantastic.”
Kane set up Lo Celso for Spurs’ second, making it nine assists in nine Premier League games this season – one more than he managed in the previous three seasons combined.
He played 22 passes in the opposition half, five more than next best Serge Aurier, while no player on the pitch was involved in more duels (14) across the 90 minutes.
Like boss Mourinho, however, the Tottenham skipper was keen to put his side’s impressive start into perspective, with 29 games to play.
“We’ll enjoy it but we know we’ve got a long way to go,” he told Sky Sports. “It’s a season where you’ve got to do all it takes to win games.
“It’s going to be an up and down year, you’ve seen that already. Part of my job is to work hard for the team, win tackles, of course score goals and getting assists.
“But I enjoy defending and working hard. The feeling now after the game once you’ve put in a great shift, there’s no better feeling when you win.
“It was a fantastic performance. We knew it was going be a tough game, Man City are a great team but we used the ball really well.
“We had a game plan to defend as a unit in that mid-block, sometimes it went into a low block, but I thought everyone worked their socks off.”
There was one blemish late on for Tottenham as they lost Toby Alderweireld to injury and Mourinho is concerned the centre-back could be facing a spell on the sidelines.
“It’s bad,” he said at his post-match media conference. “It’s a muscular injury.
“We have three centre-backs in the Premier League but not in the Europa League where we don’t have Joe Rodon.
“There’s nobody to blame. He played in matches for Belgium they needed to win. It’s just one of those things.”
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