Three or four times Hughton was quizzed about a deal, but all he would say is "Jimmy is a very good player, but I don't talk about speculation".
Celtic manager Neil Lennon is close to a deal.
Bullard could join Celtic on loan as City look to reduce their wage bill following their relegation to the npower Championship.
The 31-year-old has returned to Glasgow to visit Celtic's Lennoxtown training complex.