diff --git a/pr_agent/tools/pr_similar_issue.py b/pr_agent/tools/pr_similar_issue.py
index 7a97d85ba7..f337ebd246 100644
--- a/pr_agent/tools/pr_similar_issue.py
+++ b/pr_agent/tools/pr_similar_issue.py
@@ -17,12 +17,13 @@
 
 class PRSimilarIssue:
     def __init__(self, issue_url: str, ai_handler, args: list = None):
-        if get_settings().config.git_provider != "github":
-            raise Exception("Only github is supported for similar issue tool")
+        self.issue_url = issue_url
+        self.supported = get_settings().config.git_provider == "github"
+        if not self.supported:
+            return
 
         self.cli_mode = get_settings().CONFIG.CLI_MODE
         self.max_issues_to_scan = get_settings().pr_similar_issue.max_issues_to_scan
-        self.issue_url = issue_url
         self.git_provider = get_git_provider()()
         repo_name, issue_number = self.git_provider._parse_issue_url(issue_url.split('=')[-1])
         self.git_provider.repo = repo_name
@@ -257,6 +258,20 @@ def __init__(self, issue_url: str, ai_handler, args: list = None):
 
 
     async def run(self):
+        if not self.supported:
+            message = "The /similar_issue tool is currently supported only for GitHub."
+            if get_settings().config.publish_output:
+                try:
+                    from pr_agent.git_providers import get_git_provider_with_context
+
+                    provider = get_git_provider_with_context(self.issue_url)
+                    provider.publish_comment(message)
+                except Exception as e:
+                    get_logger().warning(
+                        "Failed to publish /similar_issue unsupported message",
+                        artifact={"error": str(e)},
+                    )
+            return ""
         get_logger().info('Getting issue...')
         repo_name, original_issue_number = self.git_provider._parse_issue_url(self.issue_url.split('=')[-1])
         issue_main = self.git_provider.repo_obj.get_issue(original_issue_number)
diff --git a/tests/unittest/test_similar_issue_non_github.py b/tests/unittest/test_similar_issue_non_github.py
new file mode 100644
index 0000000000..6581448692
--- /dev/null
+++ b/tests/unittest/test_similar_issue_non_github.py
@@ -0,0 +1,49 @@
+import pytest
+
+from pr_agent.tools.pr_similar_issue import PRSimilarIssue
+
+
+@pytest.mark.asyncio
+async def test_similar_issue_non_github_publishes_message(monkeypatch):
+    class FakeProvider:
+        def __init__(self):
+            self.comments = []
+
+        def publish_comment(self, body):
+            self.comments.append(body)
+
+    fake_provider = FakeProvider()
+
+    class FakeSettings:
+        class config:
+            git_provider = "gitlab"
+            publish_output = True
+
+    monkeypatch.setattr("pr_agent.tools.pr_similar_issue.get_settings", lambda: FakeSettings)
+    monkeypatch.setattr(
+        "pr_agent.git_providers.get_git_provider_with_context",
+        lambda _: fake_provider,
+    )
+
+    tool = PRSimilarIssue("https://gitlab.example.com/group/repo/-/merge_requests/1", None)
+    result = await tool.run()
+
+    assert result == ""
+    assert fake_provider.comments == [
+        "The /similar_issue tool is currently supported only for GitHub."
+    ]
+
+
+@pytest.mark.asyncio
+async def test_similar_issue_non_github_no_publish(monkeypatch):
+    class FakeSettings:
+        class config:
+            git_provider = "gitlab"
+            publish_output = False
+
+    monkeypatch.setattr("pr_agent.tools.pr_similar_issue.get_settings", lambda: FakeSettings)
+
+    tool = PRSimilarIssue("https://gitlab.example.com/group/repo/-/merge_requests/1", None)
+    result = await tool.run()
+
+    assert result == ""