The former Hoops defender has been linked with a return to Parkhead several times in the last few years after making a name for himself down south as manager of Everton, Manchester United and West Ham United among others.
Speaking to BBC Sportsound, Moyes admits there were approaches from the Celtic board but things never reached the next step.
He said: “Over the years there have been approaches and talks but we never got to a stage where anything got too serious.
“I think there will be a time when I choose to come back but it's always difficult in a city like Glasgow.
“I've managed in Liverpool and Manchester and it's tough. Half the city dislikes you and sometimes all the city dislikes you, depending on how you've done."