diff --git a/app/models/project.rb b/app/models/project.rb
index 4bc16771323bc312503efbea55385e630f6b8fbe..16a3f1ba649792da15886e97bd533d973a63a293 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -129,41 +129,15 @@ class Project < ApplicationRecord
   after_create :check_repository_absence!
 
   acts_as_ordered_taggable_on :topics
-  # The 'tag_list' alias and the 'has_many' associations are required during the 'tags -> topics' migration
-  # TODO: eliminate 'tag_list', 'topic_taggings' and 'tags' in the further process of the migration
-  # https://gitlab.com/gitlab-org/gitlab/-/issues/331081
+  # The 'tag_list' alias and the 'tags' association are required during the 'tags -> topics' migration
+  # TODO: eliminate 'tag_list' and 'tags' in the further process of the migration
+  # https://gitlab.com/gitlab-org/gitlab/-/issues/328226
   alias_attribute :tag_list, :topic_list
-  has_many :topic_taggings, -> { includes(:tag).order("#{ActsAsTaggableOn::Tagging.table_name}.id") },
-                     as: :taggable,
-                     class_name: 'ActsAsTaggableOn::Tagging',
-                     after_add: :dirtify_tag_list,
-                     after_remove: :dirtify_tag_list
-  has_many :topics, -> { order("#{ActsAsTaggableOn::Tagging.table_name}.id") },
-                     class_name: 'ActsAsTaggableOn::Tag',
-                     through: :topic_taggings,
-                     source: :tag
   has_many :tags, -> { order("#{ActsAsTaggableOn::Tagging.table_name}.id") },
                      class_name: 'ActsAsTaggableOn::Tag',
                      through: :topic_taggings,
                      source: :tag
 
-  # Overwriting 'topic_list' and 'topic_list=' is necessary to ensure functionality during the background migration [1].
-  # [1] https://gitlab.com/gitlab-org/gitlab/-/merge_requests/61237
-  # TODO: remove 'topic_list' and 'topic_list=' once the background migration is complete
-  # https://gitlab.com/gitlab-org/gitlab/-/issues/331081
-  def topic_list
-    # Return both old topics (context 'tags') and new topics (context 'topics')
-    tag_list_on('tags') + tag_list_on('topics')
-  end
-
-  def topic_list=(new_tags)
-    # Old topics with context 'tags' are added as new topics with context 'topics'
-    super(new_tags)
-
-    # Remove old topics with context 'tags'
-    set_tag_list_on('tags', '')
-  end
-
   attr_accessor :old_path_with_namespace
   attr_accessor :template_name
   attr_writer :pipeline_status
diff --git a/spec/models/project_spec.rb b/spec/models/project_spec.rb
index 8e606a00144fdc4f33ecb7d1c9723211bfb7472b..7b9eed7fb255793930d1d937d376bedf2c65e121 100644
--- a/spec/models/project_spec.rb
+++ b/spec/models/project_spec.rb
@@ -6888,31 +6888,6 @@ def enable_lfs
         expect(project.tags.map(&:name)).to match_array(%w[topic1 topic2 topic3])
       end
     end
-
-    context 'intermediate state during background migration' do
-      before do
-        project.taggings.first.update!(context: 'tags')
-        project.instance_variable_set("@tag_list", nil)
-        project.reload
-      end
-
-      it 'tag_list returns string array including old and new topics' do
-        expect(project.tag_list).to match_array(%w[topic1 topic2 topic3])
-      end
-
-      it 'tags returns old and new tag records' do
-        expect(project.tags.first.class.name).to eq('ActsAsTaggableOn::Tag')
-        expect(project.tags.map(&:name)).to match_array(%w[topic1 topic2 topic3])
-        expect(project.taggings.map(&:context)).to match_array(%w[tags topics topics])
-      end
-
-      it 'update tag_list adds new topics and removes old topics' do
-        project.update!(tag_list: 'topic1, topic2, topic3, topic4')
-
-        expect(project.tags.map(&:name)).to match_array(%w[topic1 topic2 topic3 topic4])
-        expect(project.taggings.map(&:context)).to match_array(%w[topics topics topics topics])
-      end
-    end
   end
 
   def finish_job(export_job)