diff --git a/src/Symfony/Component/HttpClient/Response/MockResponse.php b/src/Symfony/Component/HttpClient/Response/MockResponse.php
index c38a0a4f0cd6b..91b917f0458d4 100644
--- a/src/Symfony/Component/HttpClient/Response/MockResponse.php
+++ b/src/Symfony/Component/HttpClient/Response/MockResponse.php
@@ -38,7 +38,7 @@ class MockResponse implements ResponseInterface
     /**
      * @param string|string[]|iterable $body The response body as a string or an iterable of strings,
      *                                       yielding an empty string simulates an idle timeout,
-     *                                       exceptions are turned to TransportException
+     *                                       throwing an exception yields an ErrorChunk
      *
      * @see ResponseInterface::getInfo() for possible info, e.g. "response_headers"
      */
@@ -183,6 +183,9 @@ protected static function perform(ClientState $multi, array &$responses): void
                     $multi->handlesActivity[$id][] = null;
                     $multi->handlesActivity[$id][] = $e;
                 }
+            } elseif ($chunk instanceof \Throwable) {
+                $multi->handlesActivity[$id][] = null;
+                $multi->handlesActivity[$id][] = $chunk;
             } else {
                 // Data or timeout chunk
                 $multi->handlesActivity[$id][] = $chunk;
@@ -275,16 +278,20 @@ private static function readResponse(self $response, array $options, ResponseInt
         $body = $mock instanceof self ? $mock->body : $mock->getContent(false);
 
         if (!\is_string($body)) {
-            foreach ($body as $chunk) {
-                if ('' === $chunk = (string) $chunk) {
-                    // simulate an idle timeout
-                    $response->body[] = new ErrorChunk($offset, sprintf('Idle timeout reached for "%s".', $response->info['url']));
-                } else {
-                    $response->body[] = $chunk;
-                    $offset += \strlen($chunk);
-                    // "notify" download progress
-                    $onProgress($offset, $dlSize, $response->info);
+            try {
+                foreach ($body as $chunk) {
+                    if ('' === $chunk = (string) $chunk) {
+                        // simulate an idle timeout
+                        $response->body[] = new ErrorChunk($offset, sprintf('Idle timeout reached for "%s".', $response->info['url']));
+                    } else {
+                        $response->body[] = $chunk;
+                        $offset += \strlen($chunk);
+                        // "notify" download progress
+                        $onProgress($offset, $dlSize, $response->info);
+                    }
                 }
+            } catch (\Throwable $e) {
+                $response->body[] = $e;
             }
         } elseif ('' !== $body) {
             $response->body[] = $body;
diff --git a/src/Symfony/Component/HttpClient/Tests/MockHttpClientTest.php b/src/Symfony/Component/HttpClient/Tests/MockHttpClientTest.php
index f97b0cbb363ff..47234d71de0e9 100644
--- a/src/Symfony/Component/HttpClient/Tests/MockHttpClientTest.php
+++ b/src/Symfony/Component/HttpClient/Tests/MockHttpClientTest.php
@@ -11,6 +11,9 @@
 
 namespace Symfony\Component\HttpClient\Tests;
 
+use Symfony\Component\HttpClient\Chunk\DataChunk;
+use Symfony\Component\HttpClient\Chunk\ErrorChunk;
+use Symfony\Component\HttpClient\Chunk\FirstChunk;
 use Symfony\Component\HttpClient\Exception\TransportException;
 use Symfony\Component\HttpClient\MockHttpClient;
 use Symfony\Component\HttpClient\NativeHttpClient;
@@ -63,6 +66,46 @@ public function invalidResponseFactoryProvider()
         ];
     }
 
+    public function testThrowExceptionInBodyGenerator()
+    {
+        $mockHttpClient = new MockHttpClient([
+            new MockResponse((static function (): \Generator {
+                yield 'foo';
+                throw new TransportException('foo ccc');
+            })()),
+            new MockResponse((static function (): \Generator {
+                yield 'bar';
+                throw new \RuntimeException('bar ccc');
+            })()),
+        ]);
+
+        try {
+            $mockHttpClient->request('GET', 'https://symfony.com', [])->getContent();
+            $this->fail();
+        } catch (TransportException $e) {
+            $this->assertEquals(new TransportException('foo ccc'), $e->getPrevious());
+            $this->assertSame('foo ccc', $e->getMessage());
+        }
+
+        $chunks = [];
+        try {
+            foreach ($mockHttpClient->stream($mockHttpClient->request('GET', 'https://symfony.com', [])) as $chunk) {
+                $chunks[] = $chunk;
+            }
+            $this->fail();
+        } catch (TransportException $e) {
+            $this->assertEquals(new \RuntimeException('bar ccc'), $e->getPrevious());
+            $this->assertSame('bar ccc', $e->getMessage());
+        }
+
+        $this->assertCount(3, $chunks);
+        $this->assertEquals(new FirstChunk(0, ''), $chunks[0]);
+        $this->assertEquals(new DataChunk(0, 'bar'), $chunks[1]);
+        $this->assertInstanceOf(ErrorChunk::class, $chunks[2]);
+        $this->assertSame(3, $chunks[2]->getOffset());
+        $this->assertSame('bar ccc', $chunks[2]->getError());
+    }
+
     protected function getHttpClient(string $testCase): HttpClientInterface
     {
         $responses = [];
@@ -167,7 +210,7 @@ protected function getHttpClient(string $testCase): HttpClientInterface
             case 'testResolve':
                 $responses[] = new MockResponse($body, ['response_headers' => $headers]);
                 $responses[] = new MockResponse($body, ['response_headers' => $headers]);
-                $responses[] = new MockResponse((function () { throw new \Exception('Fake connection timeout'); yield ''; })(), ['response_headers' => $headers]);
+                $responses[] = new MockResponse((function () { yield ''; })(), ['response_headers' => $headers]);
                 break;
 
             case 'testTimeoutOnStream':