diff --git a/src/extension/chatSessions/vscode-node/copilotCLIChatSessionsContribution.ts b/src/extension/chatSessions/vscode-node/copilotCLIChatSessionsContribution.ts
index b8d8b2d46a..930d16d505 100644
--- a/src/extension/chatSessions/vscode-node/copilotCLIChatSessionsContribution.ts
+++ b/src/extension/chatSessions/vscode-node/copilotCLIChatSessionsContribution.ts
@@ -70,6 +70,20 @@ export class CopilotCLIWorktreeManager {
 		});
 	}
 
+	async createWorktreeSilently(): Promise<string | undefined> {
+		try {
+			const repository = this.gitService.activeRepository.get();
+			if (!repository) {
+				return undefined;
+			}
+			const worktreePath = await this.gitService.createWorktree(repository.rootUri);
+			return worktreePath;
+		} catch (error) {
+			// Silent failure - no warnings displayed
+			return undefined;
+		}
+	}
+
 	async storeWorktreePath(sessionId: string, workingDirectory: string): Promise<void> {
 		this._sessionWorktrees.set(sessionId, workingDirectory);
 		const sessionWorktrees = this.extensionContext.globalState.get<Record<string, string>>(CopilotCLIWorktreeManager.COPILOT_CLI_SESSION_WORKTREE_MEMENTO_KEY, {});
@@ -534,8 +548,23 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 		const history = await this.summarizer.provideChatSummary(context, token);
 
 		const requestPrompt = history ? `${prompt}\n**Summary**\n${history}` : prompt;
-		const session = await this.sessionService.createSession(requestPrompt, {}, token);
+		
+		// Create a temporary session ID to check isolation preference
+		const tempSessionId = `untitled-${Date.now()}`;
+		const isolationEnabled = this.worktreeManager.getIsolationPreference(tempSessionId);
+		
+		// Create worktree silently if isolation is enabled, before creating the session
+		const workingDirectory = isolationEnabled 
+			? await this.worktreeManager.createWorktreeSilently() ?? await this.getDefaultWorkingDirectory()
+			: await this.getDefaultWorkingDirectory();
+		
+		const session = await this.sessionService.createSession(requestPrompt, { workingDirectory, isolationEnabled }, token);
 		try {
+			// Store the worktree path for this session
+			if (workingDirectory) {
+				await this.worktreeManager.storeWorktreePath(session.object.sessionId, workingDirectory);
+			}
+			
 			await this.commandExecutionService.executeCommand('vscode.open', SessionIdForCLI.getResource(session.object.sessionId));
 			await this.commandExecutionService.executeCommand('workbench.action.chat.submit', { inputValue: requestPrompt });
 			return {};
diff --git a/src/extension/chatSessions/vscode-node/test/copilotCLIChatSessionParticipant.spec.ts b/src/extension/chatSessions/vscode-node/test/copilotCLIChatSessionParticipant.spec.ts
index d0f30d88df..652a0745a2 100644
--- a/src/extension/chatSessions/vscode-node/test/copilotCLIChatSessionParticipant.spec.ts
+++ b/src/extension/chatSessions/vscode-node/test/copilotCLIChatSessionParticipant.spec.ts
@@ -51,6 +51,7 @@ vi.mock('../copilotCLITerminalIntegration', () => {
 
 class FakeWorktreeManager extends mock<CopilotCLIWorktreeManager>() {
 	override createWorktree = vi.fn(async () => undefined);
+	override createWorktreeSilently = vi.fn(async (): Promise<string | undefined> => undefined);
 	override storeWorktreePath = vi.fn(async () => { });
 	override getWorktreePath = vi.fn((_id: string) => undefined);
 	override getIsolationPreference = vi.fn(() => false);
@@ -293,6 +294,28 @@ describe('CopilotCLIChatSessionParticipant.handleRequest', () => {
 		expect(execSpy.mock.calls[1]).toEqual(['workbench.action.chat.submit', { inputValue: expectedPrompt }]);
 	});
 
+	it('invokes handlePushConfirmationData with isolation enabled creates worktree silently', async () => {
+		// Enable isolation preference
+		worktree.getIsolationPreference = vi.fn(() => true);
+		worktree.createWorktreeSilently = vi.fn(async () => '/tmp/worktree-path');
+		
+		const request = new TestChatRequest('Push this');
+		const context = { chatSessionContext: undefined, chatSummary: undefined } as unknown as vscode.ChatContext;
+		const stream = new MockChatResponseStream();
+		const token = disposables.add(new CancellationTokenSource()).token;
+
+		await participant.createHandler()(request, context, stream, token);
+
+		// Verify worktree was created silently (not with stream parameter)
+		expect(worktree.createWorktreeSilently).toHaveBeenCalledTimes(1);
+		expect(worktree.createWorktree).not.toHaveBeenCalled();
+		
+		// Verify worktree path was stored
+		expect(worktree.storeWorktreePath).toHaveBeenCalledTimes(1);
+		const sessionId = Array.from(manager.sessions.keys())[0];
+		expect(worktree.storeWorktreePath).toHaveBeenCalledWith(sessionId, '/tmp/worktree-path');
+	});
+
 	it('handleConfirmationData accepts uncommitted-changes and records push', async () => {
 		// Existing session (non-untitled) so confirmation path is hit
 		const sessionId = 'existing-confirm';