diff --git a/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenGCSImage.swift b/FirebaseVertexAI/Sources/Types/Internal/Imagen/ImagenGCSImage.swift
similarity index 95%
rename from FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenGCSImage.swift
rename to FirebaseVertexAI/Sources/Types/Internal/Imagen/ImagenGCSImage.swift
index a4c1458b19c..8715cbb12bd 100644
--- a/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenGCSImage.swift
+++ b/FirebaseVertexAI/Sources/Types/Internal/Imagen/ImagenGCSImage.swift
@@ -15,8 +15,10 @@
 import Foundation
 
 /// An image generated by Imagen, stored in Cloud Storage (GCS) for Firebase.
+///
+/// TODO(#14451): Make this `public` and move to the `Public` directory when ready.
 @available(iOS 15.0, macOS 12.0, macCatalyst 15.0, tvOS 15.0, watchOS 8.0, *)
-public struct ImagenGCSImage {
+struct ImagenGCSImage {
   /// The IANA standard MIME type of the image file; either `"image/png"` or `"image/jpeg"`.
   ///
   /// > Note: To request a different format, set ``ImagenGenerationConfig/imageFormat`` in
diff --git a/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenGenerationResponse.swift b/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenGenerationResponse.swift
index b783cb909c8..de0f0c06c38 100644
--- a/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenGenerationResponse.swift
+++ b/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenGenerationResponse.swift
@@ -16,14 +16,15 @@ import Foundation
 
 /// A response from a request to generate images with Imagen.
 ///
-/// The type placeholder `T` is an image type of either ``ImagenInlineImage`` or ``ImagenGCSImage``.
+/// The type placeholder `T` is an image type; this is currently always an ``ImagenInlineImage``.
 ///
 /// This type is returned from:
 ///   - ``ImagenModel/generateImages(prompt:)`` where `T` is ``ImagenInlineImage``
-///   - ``ImagenModel/generateImages(prompt:gcsURI:)`` where `T` is ``ImagenGCSImage``
 @available(iOS 15.0, macOS 12.0, macCatalyst 15.0, tvOS 15.0, watchOS 8.0, *)
+// TODO(#14451): Re-add "- ``ImagenModel/generateImages(prompt:gcsURI:)`` where `T` is
+//                         ``ImagenGCSImage``" in the DocC above.
 public struct ImagenGenerationResponse<T> {
-  /// The images generated by Imagen; see ``ImagenInlineImage`` and ``ImagenGCSImage``.
+  /// The images generated by Imagen; see ``ImagenInlineImage``.
   ///
   /// > Important: The number of images generated may be fewer than the number requested if one or
   ///   more were filtered out; see ``filteredReason``.
diff --git a/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenModel.swift b/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenModel.swift
index 0694c4f496a..2196d4c6040 100644
--- a/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenModel.swift
+++ b/FirebaseVertexAI/Sources/Types/Public/Imagen/ImagenModel.swift
@@ -110,7 +110,9 @@ public final class ImagenModel {
   ///   - prompt: A text prompt describing the image(s) to generate.
   ///   - gcsURI: The Cloud Storage (GCS) for Firebase URI where the generated images are stored.
   ///     This is a `"gs://"`-prefixed URI , for example, `"gs://bucket-name/path/"`.
-  public func generateImages(prompt: String, gcsURI: String) async throws
+  ///
+  /// TODO(#14451): Make this `public` when backend support is ready.
+  func generateImages(prompt: String, gcsURI: String) async throws
     -> ImagenGenerationResponse<ImagenGCSImage> {
     return try await generateImages(
       prompt: prompt,
diff --git a/FirebaseVertexAI/Tests/TestApp/Tests/Integration/ImagenIntegrationTests.swift b/FirebaseVertexAI/Tests/TestApp/Tests/Integration/ImagenIntegrationTests.swift
index 29ddcab71e2..fc07ff8acef 100644
--- a/FirebaseVertexAI/Tests/TestApp/Tests/Integration/ImagenIntegrationTests.swift
+++ b/FirebaseVertexAI/Tests/TestApp/Tests/Integration/ImagenIntegrationTests.swift
@@ -23,6 +23,9 @@ import VertexAITestApp
   import UIKit
 #endif // canImport(UIKit)
 
+// TODO(#14452): Remove `@testable import` when `generateImages(prompt:gcsURI:)` is public.
+@testable import class FirebaseVertexAI.ImagenModel
+
 @Suite(
   .enabled(
     if: ProcessInfo.processInfo.environment["VTXIntegrationImagen"] != nil,