Speaking exclusively to Football Insider, the ex-Premier League and England defender insisted “it is not right” that there have not been any away fans in recent games between the two sides.
As quoted by Sky Sports on Tuesday (15 February), Rangers managing director Stewart Robertson claimed there will be away fans at the remaining two Old Firm fixtures of the season.
However, Celtic tweeted on Thursday (17 February) that they will determine the allocation for the next game at Parkhead and will communicate their decision at the appropriate time.
The two games between the sides earlier this season took place in front of capacity home crowds.
“Somebody has to step in and sort this out properly,” Mills told Football Insider‘s Connor Whitley.
“Whether that be the Scottish FA or the government, whoever it might be. It’s not right.
“There are always been issues between certain clubs and certain fans but it can be policed very well.
“Even if you have to ship people in. They might have to meet five miles out of town at a retail park or a service station and they can get bussed in and bussed out. Ok, there’s an extra expense in that.
“I remember when Leeds and Millwall had issues, you had to go and collect your ticket three hours before the game at a service station south of Leeds. Then you got on a bus and were taken to the game.
“It might be a hassle and it might be an inconvenience but there has to be some sort of way around this to get fans back in.”