No. Not as far as I know anyway.
This comes up, regularly, in various forms. (Usually "how do I make a unit change sides?" The workarounds are to combine setCaptive commands and the following trick in whichever way gets closest to what you want.
Create a West officer. Set his probability of presence to 0. Create a Resistance soldier. Group him under the West officer. He will now be on side West. Works for all combinations including civvies.
The other relevant fact is that civilians with weapons will shoot at whatever side Resistance is not friendly to, but that side will not shoot back.