Coleman named Bale in his squad to face Giovani Trapattoni's side on Wednesday and the winger trained with the squad ahead of the match.
Bale has been linked with a move to Real Madrid during the off-season and has not taken part in the latter stages of Tottenham's pre-season campaign.
His absence was reported to be due to a foot injury but the 43-year-old admitted Bale would have been able to play had his fitness levels been higher.
"We are not here to get in the way but if Gareth had a chance of playing he would be playing," Coleman said.
"The reason he is not playing is because mentally he is not ready and physically he is not ready to play.
"He has not been training at Tottenham and not enough sessions. This is not just for Gareth but any player, it is too risky. We have got a good medical team and after having talks with them the feeling was that it is too much of a risk.
"Whatever Tottenham Hotspur and Gareth Bale decide to do and whether he stays or goes is nothing to do with me, my job is when he comes with Wales and how he plays and is with us and that is all fantastic the other side is between Gareth and Tottenham."
Bale has been Wales' talisman in recent internationals, scoring seven of their last 13 goals.
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