Scotland face Denmark next week meaning City's new signing will be on duty for his country rather than for Cardiff who play at Oxford in the Carling Cup.
City are not short of potential Scottish internationals with Kevin McNaughton, Don Cowie, Craig Conway, David Marshall and Paul Quinn on the payroll but Miller is the only one called up this time.
Wales are also playing next week. When City kick off at the Kassam Stadium, Oxford - Wales will be playing at CCS against Australia. Gary Speed will be at The Eisteddfod in Wrexham on Friday and will name his squad from there.
Wales U21's are also in action on the same night at Haverfordwest. Cardiff's Jon Meades is on stand by for that squad.