diff --git a/src/Symfony/Component/HttpClient/HttpClientTrait.php b/src/Symfony/Component/HttpClient/HttpClientTrait.php
index c8351f55bc2ba..1f5dc4d012756 100644
--- a/src/Symfony/Component/HttpClient/HttpClientTrait.php
+++ b/src/Symfony/Component/HttpClient/HttpClientTrait.php
@@ -23,6 +23,7 @@
 trait HttpClientTrait
 {
     private static $CHUNK_SIZE = 16372;
+    private static $emptyDefaults;
 
     /**
      * Validates and normalizes method, URL and options, and merges them with defaults.
@@ -40,6 +41,16 @@ private static function prepareRequest(?string $method, ?string $url, array $opt
             }
         }
 
+        if (null === self::$emptyDefaults) {
+            self::$emptyDefaults = [];
+
+            foreach ($defaultOptions as $k => $v) {
+                if (null !== $v) {
+                    self::$emptyDefaults[$k] = $v;
+                }
+            }
+        }
+
         $options = self::mergeDefaultOptions($options, $defaultOptions, $allowExtraOptions);
 
         $buffer = $options['buffer'] ?? true;
@@ -189,6 +200,16 @@ private static function mergeDefaultOptions(array $options, array $defaultOption
 
         $options += $defaultOptions;
 
+        if (null === self::$emptyDefaults) {
+            self::$emptyDefaults = [];
+        }
+
+        foreach (self::$emptyDefaults as $k => $v) {
+            if (!isset($options[$k])) {
+                $options[$k] = $v;
+            }
+        }
+
         if (isset($defaultOptions['extra'])) {
             $options['extra'] += $defaultOptions['extra'];
         }
@@ -221,9 +242,9 @@ private static function mergeDefaultOptions(array $options, array $defaultOption
 
             $alternatives = [];
 
-            foreach ($defaultOptions as $key => $v) {
-                if (levenshtein($name, $key) <= \strlen($name) / 3 || str_contains($key, $name)) {
-                    $alternatives[] = $key;
+            foreach ($defaultOptions as $k => $v) {
+                if (levenshtein($name, $k) <= \strlen($name) / 3 || str_contains($k, $name)) {
+                    $alternatives[] = $k;
                 }
             }
 
diff --git a/src/Symfony/Component/HttpClient/Tests/CurlHttpClientTest.php b/src/Symfony/Component/HttpClient/Tests/CurlHttpClientTest.php
index e932470d2a98c..dd5bef04d08ae 100644
--- a/src/Symfony/Component/HttpClient/Tests/CurlHttpClientTest.php
+++ b/src/Symfony/Component/HttpClient/Tests/CurlHttpClientTest.php
@@ -148,6 +148,17 @@ public function testHandleIsReinitOnReset()
         self::assertNotSame($initialShareId, $clientState->share);
     }
 
+    public function testNullBody()
+    {
+        $httpClient = $this->getHttpClient(__FUNCTION__);
+
+        $httpClient->request('POST', 'http://localhost:8057/post', [
+            'body' => null,
+        ]);
+
+        $this->expectNotToPerformAssertions();
+    }
+
     public function testProcessAfterReset()
     {
         $client = $this->getHttpClient(__FUNCTION__);