How to assign a list of strings from jenkins pipeline to tfvars file variable

I have created a pipeline which deploys ec2 instances based on choices provided by multi select parameter from jenkins pipeline.
Based on some operations, I will be generating list subnet_ids for corresponding aws availability zones. I am not able assign this list of subnet_ids to the vpc_zone_identifier variable in env.tfvars file.

subnet_ids : ["id1’,"id2’’,"id3’]

vpc_zone_identifier = ["${var.subnet_ids}"]

How can I achieve this