diff --git a/Earthfile b/Earthfile
index 2403502..a5e78b9 100644
--- a/Earthfile
+++ b/Earthfile
@@ -10,7 +10,7 @@ ARG IMAGE_REGISTRY
 ARG IMAGE_REPO=$OS_DISTRIBUTION
 ARG K8S_DISTRIBUTION
 ARG CUSTOM_TAG
-ARG CLUSTERCONFIG=spc.tgz
+ARG CLUSTERCONFIG
 ARG ARCH
 ARG PE_VERSION=v4.2.1
 ARG SPECTRO_LUET_VERSION=v1.2.0
@@ -138,7 +138,9 @@ build-iso:
     COPY overlay/files-iso/ /overlay/
     COPY --if-exists user-data /overlay/files-iso/config.yaml
     COPY --if-exists content-*/*.zst /overlay/opt/spectrocloud/content/
-    COPY --if-exists $CLUSTERCONFIG /overlay/opt/spectrocloud/clusterconfig/spc.tgz
+    IF [ "$CLUSTERCONFIG" != ""]
+        COPY --if-exists $CLUSTERCONFIG /overlay/opt/spectrocloud/clusterconfig/spc.tgz
+    END
     WORKDIR /build
     COPY --platform=linux/${ARCH} --keep-own +iso-image-rootfs/rootfs /build/image
     IF [ "$ARCH" = "arm64" ]
diff --git a/README.md b/README.md
index 34bd9c6..55fc715 100644
--- a/README.md
+++ b/README.md
@@ -132,7 +132,7 @@ Skip this step if your base image is ubuntu or opensuse-leap. If you are buildin
 | NO_PROXY         | URLS that should be excluded from proxying (Optional)                                                                                                                                                                                                                                                                                          | string |                         |
 | PROXY_CERT_PATH  | Absolute path of the SSL Proxy certificate in PEM format if needed (Optional)                                                                                                                                                                                                                                                                  | string |                         |
 | UPDATE_KERNEL    | Determines whether to upgrade the Kernel version to the latest from the upstream OS provider                                                                                                                                                                                                                                                   | boolean| `false`                 |
-| CLUSTERCONFIG    | Path of the cluster config | string | `spc.tgz` |
+| CLUSTERCONFIG    | Path of the cluster config | string |  |
 
 8. (Optional) If you are building the images behind a proxy server, you may need to modify your docker daemon settings to let it use your proxy server. You can refer this [tutorial](https://docs.docker.com/config/daemon/systemd/#httphttps-proxy).