diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 695df12..44965f1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,6 +20,7 @@ jobs:
         uses: actions/setup-node@v3
         with:
           node-version: ${{ matrix.node-version }}
+      - run: echo "${{ secrets.GITHUB_TOKEN }}" | docker login ghcr.io -u $ --password-stdin
       - run: npm ci
       - run: npm run lint
       - run: npm test
diff --git a/README.md b/README.md
index 0fc69ba..b890554 100644
--- a/README.md
+++ b/README.md
@@ -76,6 +76,20 @@ _Optional_ Use `additional-docker-arguments` if you need to provide additional a
         additional-docker-arguments: --build-arg env=staging
 ```
 
+### `external-registry-url`
+
+_Optional_ Push the image to an external container registry. This registry does not need to be [registered with Humanitec](https://docs.humanitec.com/guides/connect-ci-setup/container-registries) and authentication needs to be done before calling this action (e.g. using workload identity). 
+
+```yaml
+    uses: humanitec/build-push-to-humanitec@v1
+      with:
+        humanitec-token: ${{ secrets.HUMANITEC_TOKEN }}
+        organization: awesome-company
+        external-registry-url: europe-west3-docker.pkg.dev/gcp-project/repository
+```
+
+Will push the resulting image to `europe-west3-docker.pkg.dev/gcp-project/repository/{image-name}`.
+
 ## Outputs
 
 _None._
diff --git a/action.test.ts b/action.test.ts
index 32dc950..b98e37b 100644
--- a/action.test.ts
+++ b/action.test.ts
@@ -132,4 +132,30 @@ describe('action', () => {
       ),
     );
   });
+
+  test('supports an external registry', async () => {
+    repo = 'test-image';
+    process.env['GITHUB_REPOSITORY'] = repo;
+
+    setInput('external-registry-url', 'ghcr.io/humanitec/build-push-to-humanitec');
+
+    await runAction();
+    expect(process.exitCode).toBeFalsy;
+
+    const res = await humanitecReq(`orgs/${orgId}/artefact-versions`, {method: 'GET'});
+    expect(res.status).toBe(200);
+
+    const body = await res.json();
+
+    expect(body).toEqual(
+      expect.arrayContaining(
+        [
+          expect.objectContaining({
+            commit: commit,
+            name: `ghcr.io/humanitec/build-push-to-humanitec/${repo}`,
+          }),
+        ],
+      ),
+    );
+  });
 });
diff --git a/action.ts b/action.ts
index 49a1f4e..8f72235 100644
--- a/action.ts
+++ b/action.ts
@@ -14,12 +14,13 @@ export async function runAction() {
   const imageName = core.getInput('image-name') || (process.env.GITHUB_REPOSITORY || '').replace(/.*\//, '');
   const context = core.getInput('context') || core.getInput('dockerfile') || '.';
   const file = core.getInput('file') || '';
-  const registryHost = core.getInput('humanitec-registry') || 'registry.humanitec.io';
+  let registryHost = core.getInput('humanitec-registry') || 'registry.humanitec.io';
   const apiHost = core.getInput('humanitec-api') || 'api.humanitec.io';
   const tag = core.getInput('tag') || '';
   const commit = process.env.GITHUB_SHA || '';
   const autoTag = /^\s*(true|1)\s*$/i.test(core.getInput('auto-tag'));
   const additionalDockerArguments = core.getInput('additional-docker-arguments') || '';
+  const externalRegistryUrl = core.getInput('external-registry-url') || '';
 
   const ref = process.env.GITHUB_REF || '';
   if (!existsSync(`${process.env.GITHUB_WORKSPACE}/.git`)) {
@@ -44,20 +45,25 @@ export async function runAction() {
 
   const humanitec = humanitecFactory(token, orgId, apiHost);
 
-  let registryCreds;
-  try {
-    registryCreds = await humanitec.getRegistryCredentials();
-  } catch (error) {
-    core.error('Unable to fetch repository credentials.');
-    core.error('Did you add the token to your Github Secrets? ' +
+  if (externalRegistryUrl == '') {
+    let registryCreds;
+    try {
+      registryCreds = await humanitec.getRegistryCredentials();
+    } catch (error) {
+      core.error('Unable to fetch repository credentials.');
+      core.error('Did you add the token to your Github Secrets? ' +
       'http:/docs.humanitec.com/connecting-your-ci#github-actions');
-    core.setFailed('Unable to access Humanitec.');
-    return;
-  }
+      core.setFailed('Unable to access Humanitec.');
+      return;
+    }
 
-  if (!docker.login(registryCreds.username, registryCreds.password, registryHost)) {
-    core.setFailed('Unable to connect to the humanitec registry.');
-    return;
+    if (!docker.login(registryCreds.username, registryCreds.password, registryHost)) {
+      core.setFailed('Unable to connect to the humanitec registry.');
+      return;
+    }
+    registryHost = `${registryHost}/${orgId}`;
+  } else {
+    registryHost = externalRegistryUrl;
   }
 
   process.chdir((process.env.GITHUB_WORKSPACE || ''));
@@ -70,21 +76,22 @@ export async function runAction() {
   } else {
     version = commit;
   }
-  const localTag = `${orgId}/${imageName}:${version}`;
+  const imageWithVersion = `${imageName}:${version}`;
+  const localTag = `${orgId}/${imageWithVersion}`;
   const imageId = await docker.build(localTag, file, additionalDockerArguments, context);
   if (!imageId) {
     core.setFailed('Unable build image from Dockerfile.');
     return;
   }
 
-  const remoteTag = `${registryHost}/${localTag}`;
+  const remoteTag = `${registryHost}/${imageWithVersion}`;
   if (!docker.push(imageId, remoteTag)) {
     core.setFailed('Unable to push image to registry');
     return;
   }
 
   const payload = {
-    name: `${registryHost}/${orgId}/${imageName}`,
+    name: `${registryHost}/${imageName}`,
     type: 'container',
     version,
     ref,
diff --git a/action.yaml b/action.yaml
index 8e2e62e..ced87c5 100644
--- a/action.yaml
+++ b/action.yaml
@@ -38,6 +38,10 @@ inputs:
     description: 'Allows the default humanitec api to be overidden for testing.'
     required: false
     default: 'api.humanitec.io'
+  external-registry-url:
+    description: 'Push the image to an external container registry. This registry does not need to be [registered with Humanitec](https://docs.humanitec.com/guides/connect-ci-setup/container-registries) and authentication needs to be done by the explicitly (e.g. using workload identity).'
+    required: false
+    default: ''
 runs:
   using: 'node16'
   main: 'dist/index.js'
diff --git a/chunk.ts b/chunk.ts
deleted file mode 100644
index e310f48..0000000
--- a/chunk.ts
+++ /dev/null
@@ -1,68 +0,0 @@
-export const args = (str: string): string[] => {
-  const args = [];
-  str = str.trim();
-  let currentArg = '';
-  for (let i = 0; i < str.length; i++) {
-    switch (str[i]) {
-      case '\'':
-        const endQuoteIndex = str.indexOf('\'', i+1);
-        if (endQuoteIndex < 0) {
-          throw 'single quote not closed';
-        }
-        currentArg = currentArg + str.substring(i+1, endQuoteIndex);
-        i = endQuoteIndex;
-        break;
-      case '"':
-        // Double quotes can contain escaped characters
-        for (i++; i < str.length && str[i] !== '"'; i++) {
-          if (str[i] === '\\' && (i+1) < str.length) {
-            i++;
-            switch (str[i]) {
-              case 'n':
-                currentArg += '\n';
-                break;
-              case 'r':
-                currentArg += '\r';
-                break;
-              case 't':
-                currentArg += '\t';
-                break;
-              default:
-                currentArg += str[i];
-            }
-          } else {
-            currentArg += str[i];
-          }
-        }
-        if (i >= str.length) {
-          throw 'double quote not closed';
-        }
-        break;
-      case ' ':
-      case '\t':
-        args.push(currentArg);
-        currentArg = '';
-        while (i < str.length && (str[i] === ' ' || str[i] === '\t')) {
-          i++;
-        }
-        // We will have advanced to the next non-whitespace
-        i--;
-        break;
-      case '\\':
-        i++;
-        if (i < str.length) {
-          currentArg = currentArg + str[i];
-        } else {
-          throw 'uncompleted escape character';
-        }
-        break;
-      default:
-        currentArg = currentArg + str[i];
-        break;
-    }
-  }
-  if (currentArg != '') {
-    args.push(currentArg);
-  }
-  return args;
-}
diff --git a/dist/index.js b/dist/index.js
index 89a4edd..15adac7 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -7773,12 +7773,13 @@ async function runAction() {
     const imageName = core.getInput('image-name') || (process.env.GITHUB_REPOSITORY || '').replace(/.*\//, '');
     const context = core.getInput('context') || core.getInput('dockerfile') || '.';
     const file = core.getInput('file') || '';
-    const registryHost = core.getInput('humanitec-registry') || 'registry.humanitec.io';
+    let registryHost = core.getInput('humanitec-registry') || 'registry.humanitec.io';
     const apiHost = core.getInput('humanitec-api') || 'api.humanitec.io';
     const tag = core.getInput('tag') || '';
     const commit = process.env.GITHUB_SHA || '';
     const autoTag = /^\s*(true|1)\s*$/i.test(core.getInput('auto-tag'));
     const additionalDockerArguments = core.getInput('additional-docker-arguments') || '';
+    const externalRegistryUrl = core.getInput('external-registry-url') || '';
     const ref = process.env.GITHUB_REF || '';
     if (!(0, node_fs_1.existsSync)(`${process.env.GITHUB_WORKSPACE}/.git`)) {
         core.error('It does not look like anything was checked out.');
@@ -7798,20 +7799,26 @@ async function runAction() {
         return;
     }
     const humanitec = (0, humanitec_1.humanitecFactory)(token, orgId, apiHost);
-    let registryCreds;
-    try {
-        registryCreds = await humanitec.getRegistryCredentials();
-    }
-    catch (error) {
-        core.error('Unable to fetch repository credentials.');
-        core.error('Did you add the token to your Github Secrets? ' +
-            'http:/docs.humanitec.com/connecting-your-ci#github-actions');
-        core.setFailed('Unable to access Humanitec.');
-        return;
+    if (externalRegistryUrl == '') {
+        let registryCreds;
+        try {
+            registryCreds = await humanitec.getRegistryCredentials();
+        }
+        catch (error) {
+            core.error('Unable to fetch repository credentials.');
+            core.error('Did you add the token to your Github Secrets? ' +
+                'http:/docs.humanitec.com/connecting-your-ci#github-actions');
+            core.setFailed('Unable to access Humanitec.');
+            return;
+        }
+        if (!docker.login(registryCreds.username, registryCreds.password, registryHost)) {
+            core.setFailed('Unable to connect to the humanitec registry.');
+            return;
+        }
+        registryHost = `${registryHost}/${orgId}`;
     }
-    if (!docker.login(registryCreds.username, registryCreds.password, registryHost)) {
-        core.setFailed('Unable to connect to the humanitec registry.');
-        return;
+    else {
+        registryHost = externalRegistryUrl;
     }
     process.chdir((process.env.GITHUB_WORKSPACE || ''));
     let version = '';
@@ -7824,19 +7831,20 @@ async function runAction() {
     else {
         version = commit;
     }
-    const localTag = `${orgId}/${imageName}:${version}`;
+    const imageWithVersion = `${imageName}:${version}`;
+    const localTag = `${orgId}/${imageWithVersion}`;
     const imageId = await docker.build(localTag, file, additionalDockerArguments, context);
     if (!imageId) {
         core.setFailed('Unable build image from Dockerfile.');
         return;
     }
-    const remoteTag = `${registryHost}/${localTag}`;
+    const remoteTag = `${registryHost}/${imageWithVersion}`;
     if (!docker.push(imageId, remoteTag)) {
         core.setFailed('Unable to push image to registry');
         return;
     }
     const payload = {
-        name: `${registryHost}/${orgId}/${imageName}`,
+        name: `${registryHost}/${imageName}`,
         type: 'container',
         version,
         ref,