Error: Invalid AWS Region: ap-southeast-4

When trying to run terraform init for an AWS configuration where the backend is in the new region ap-southeast-4 (Australia/Melbourne), backend initialisation fails with the error

Error: Invalid AWS Region: ap-southeast-4.

Support for this region was added in provider version 4.54.0, which I have upgraded to.

The backend configuration looks like this (values redacted):

terraform {
  required_version = ">= 1.2.1"
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "4.54.0"

  backend "s3" {
    key            = "<object_key>"
    bucket         = "<bucket_name>"
    dynamodb_table = "<dynamodb_name>"
    region         = "ap-southeast-4"
    acl            = "private"
    encrypt        = "true"
    role_arn       = "<role_arn>"

If I change region to anything else, this error does not occur.

Just posting here to determine if it’s a bug that I should post on GitHub, or if I am doing something else wrong.

Thank you in advance.

What version of Terraform are you using? As you are using an S3 backend you also need region support in Terraform core as well as the AWS provider.

Thank you, I wasn’t aware of that. I will update my Terraform binary and proceed.

Still happening with Terraform 1.3.8.

Using skip_region_validation = true in the backend config provides a workaround.