@anil kumar , Sorry I missed to add the region limitation over there. Yes, you can associate any number of subnets to a route table if corresponding VNETs and route table are under same region.
Actually what I was asking why there isn't a easy way recreate a route table into another region --> As of today we have only few Azure services to move across regions and our team is actively working on them to extend. For now, we have only two moving options on RT (i.e.) across Subscriptions or Resource groups.
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