diff --git a/src/Symfony/Component/Validator/Constraints/IbanValidator.php b/src/Symfony/Component/Validator/Constraints/IbanValidator.php
index 1afc8f01b7..3ec4c6ea7a 100644
--- a/src/Symfony/Component/Validator/Constraints/IbanValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/IbanValidator.php
@@ -30,6 +30,13 @@ class IbanValidator extends ConstraintValidator
             return;
         }
 
+        // An IBAN without a country code is not an IBAN.
+        if (0 === preg_match('/[A-Za-z]/', $value)) {
+            $this->context->addViolation($constraint->message, array('{{ value }}' => $value));
+
+            return;
+        }
+
         $teststring = preg_replace('/\s+/', '', $value);
 
         if (strlen($teststring) < 4) {
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/IbanValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/IbanValidatorTest.php
index cfd9f2cd8f..eae04e352f 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/IbanValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/IbanValidatorTest.php
@@ -182,6 +182,7 @@ class IbanValidatorTest extends \PHPUnit_Framework_TestCase
             array('CY170020 128 0000 0012 0052 7600'),
             array('foo'),
             array('123'),
+            array('0750447346')
         );
     }
 }