diff --git a/rules-tests/DeadCode/Rector/Property/RemoveDefaultValueFromAssignedPropertyRector/Fixture/skip_nested_conditional_assign.php.inc b/rules-tests/DeadCode/Rector/Property/RemoveDefaultValueFromAssignedPropertyRector/Fixture/skip_nested_conditional_assign.php.inc
new file mode 100644
index 00000000000..c01cc6597c4
--- /dev/null
+++ b/rules-tests/DeadCode/Rector/Property/RemoveDefaultValueFromAssignedPropertyRector/Fixture/skip_nested_conditional_assign.php.inc
@@ -0,0 +1,21 @@
+<?php
+
+namespace Rector\Tests\DeadCode\Rector\Property\RemoveDefaultValueFromAssignedPropertyRector\Fixture;
+
+final class SkipNestedConditionalAssign
+{
+    private string $a = '';
+
+    public function __construct(bool $value)
+    {
+        if ($value) {
+            if (mt_rand(0, 1)) {
+                $this->a = 'a';
+            } else {
+                $this->a = 'b';
+            }
+        }
+
+        echo $this->a;
+    }
+}
diff --git a/rules/TypeDeclaration/AlreadyAssignDetector/ConstructorAssignDetector.php b/rules/TypeDeclaration/AlreadyAssignDetector/ConstructorAssignDetector.php
index 52229f55273..66da7da3146 100644
--- a/rules/TypeDeclaration/AlreadyAssignDetector/ConstructorAssignDetector.php
+++ b/rules/TypeDeclaration/AlreadyAssignDetector/ConstructorAssignDetector.php
@@ -132,6 +132,11 @@ private function isIfElseAssign(Node $node, string $propertyName): bool
             return false;
         }
 
+        // nested if/else does not guarantee the assign, the outer condition can skip it
+        if ($node->getAttribute(AttributeKey::IS_FIRST_LEVEL_STATEMENT) !== true) {
+            return false;
+        }
+
         return $this->isAssignedInStmts($node->stmts, $propertyName) && $this->isAssignedInStmts(
             $node->else->stmts,
             $propertyName