diff --git a/tensorflow/lite/core/subgraph.cc b/tensorflow/lite/core/subgraph.cc
index 81710df128b..0f11af51488 100644
--- a/tensorflow/lite/core/subgraph.cc
+++ b/tensorflow/lite/core/subgraph.cc
@@ -1323,6 +1323,20 @@ TfLiteStatus Subgraph::RemoveAllDelegates() {
 
 bool Subgraph::HasDelegates() { return !delegates_applied_.empty(); }
 
+void Subgraph::EnsureTensorsVectorCapacity() {
+  const size_t required_capacity = tensors_.size() + kTensorsCapacityHeadroom;
+  if (required_capacity > tensors_.capacity()) {
+    // Whenever it's required to increase the vector capacity, make it at
+    // least twice bigger. The behavior is consistent with the default
+    // behavior of GCC STL's `std::vector::resize()`. This avoids frequently
+    // allocating and copying the underlying buffer.
+    size_t reserved_capacity =
+        std::max(required_capacity, tensors_.capacity() * 2);
+    tensors_.reserve(reserved_capacity);
+    context_.tensors = tensors_.data();
+  }
+}
+
 TfLiteStatus Subgraph::EnsureMemoryAllocations() {
   if (memory_planner_) {
     state_ = kStateUninvokable;
diff --git a/tensorflow/lite/core/subgraph.h b/tensorflow/lite/core/subgraph.h
index d9ccff35105..bee13c9073e 100644
--- a/tensorflow/lite/core/subgraph.h
+++ b/tensorflow/lite/core/subgraph.h
@@ -567,19 +567,7 @@ class Subgraph {
   // capacity. Calling this function may invalidate existing pointers to
   // tensors. After calling this function, adding `kTensorsCapacityHeadroom`
   // more tensors won't invalidate the pointer to existing tensors.
-  void EnsureTensorsVectorCapacity() {
-    const size_t required_capacity = tensors_.size() + kTensorsCapacityHeadroom;
-    if (required_capacity > tensors_.capacity()) {
-      // Whenever it's required to increase the vector capacity, make it at
-      // least twice bigger. The behavior is consistent with the default
-      // behavior of GCC STL's `std::vector::resize()`. This avoids frequently
-      // allocating and copying the underlying buffer.
-      size_t reserved_capacity =
-          std::max(required_capacity, tensors_.capacity() * 2);
-      tensors_.reserve(reserved_capacity);
-      context_.tensors = tensors_.data();
-    }
-  }
+  void EnsureTensorsVectorCapacity();
 
   // Ensures the memory required is planned and allocated.
   TfLiteStatus EnsureMemoryAllocations();