Reports over the summer claimed that Spurs had agreed personal terms with the Portugal playmaker following a campaign in which he scored 20 goals and laid on 13 assists.
However, it was confirmed last week that Fernandes had signed a new four-year contract at Sporting, who he joined from Sampdoria in 2017, which included an updated £85m release clause.
Speaking on the subject of Fernandes, Mourinho told Sport TV: “We are different club at this level.
“We are not a club that is going to make big transfers in the market, nor is it going towards players who are already developed or at a certain level of expectation, also economically.
“I would definitely say no because Bruno (Fernandes) is a player of a level and value that is not for us.”
The news is somewhat of a surprise given that Spurs are in the market for midfield reinforcements due to the impending exit of Christian Eriksen, who has reportedly told Mourinho that he will leave on a free when his contract runs out next summer.