The 31-year-old England striker was substituted in the 33rd minute of QPR’s goalless draw with Chelsea on Saturday after suffering cruciate ligament damage which is expected to keep him sidelined for most of the season.
QPR were reported to have already taken steps to find a temporary replacement for Johnson in January, with City’s promising young striker Guidetti a touted target for the Hoops.
However, Hughes revealed the west London outfit have not been in touch with the Premier League champions over a possible deal for the Sweden international, who scored 20 goals for Feyenoord last season.
“It’s just speculation,” said Hughes. “I saw that myself. To my knowledge, we’ve not made any contact as a consequence of Andy [Johnson] being injured.
“There may have been conversations surrounding a number of players prior to the window closing, but since Andy has been injured, we haven’t made any contact in terms of trying to get someone in.
“Either way, we won’t be able to do anything until the January transfer window.
“I’m sure there’ll be discussions, but to my knowledge that there’s not been any contact with Manchester City.”
Johnson, who was signed on a free transfer in July, was impressive in his 33-minute cameo for QPR against the Blues before suffering the injury setback.
Hughes admitted the striker’s injury was a blow to the club, but the 48-year-old is confident QPR have enough strength in depth to cope with Johnson’s absence.
“We’re upset for Andy and for ourselves as a club because in the short time he’s been with us, people have seen why I brought him to the club and the qualities that he has.
“Unfortunately we’re not going to be able to use those qualities for a significant amount of time.
“His energy and undoubted ability are going to be a loss for us.
“Obviously you want to build the squad to be able to cope when you do have long-term injuries and the absence of Andy will allow other players to come to the fore.”