diff --git a/src/ShapeClipboard.ts b/src/ShapeClipboard.ts
index 5900d9c..053cd59 100644
--- a/src/ShapeClipboard.ts
+++ b/src/ShapeClipboard.ts
@@ -42,6 +42,7 @@ interface PasteContext {
   binaryModifications: Map<string, Uint8Array>;
   contentTypesDocument: XMLDocument;
   clonedParts: Map<string, string>;
+  parsedDocuments: Map<string, XMLDocument>;
 }
 
 export function createSlideObjectClipboard(
@@ -122,7 +123,8 @@ export async function pasteSlideObjects(
     textModifications: new Map(),
     binaryModifications: new Map(),
     contentTypesDocument,
-    clonedParts: new Map()
+    clonedParts: new Map(),
+    parsedDocuments: new Map()
   };
   const destinationShapeTree = getShapeTree(destinationSlideDocument);
   const shapeIndexes: number[] = [];
@@ -134,11 +136,15 @@ export async function pasteSlideObjects(
 
     offsetShape(clonedShape, offsetEmu, offsetEmu);
     assignUniqueNonVisualIds(destinationSlideDocument, clonedShape);
-    await copyShapeRelationships(sourceSlidePath, destinationSlidePath, clonedShape, context);
+    copyShapeRelationships(sourceSlidePath, destinationSlidePath, clonedShape, context);
     destinationShapeTree.appendChild(clonedShape);
     shapeIndexes.push(getShapeChildren(destinationShapeTree).length - 1);
   }
 
+  for (const [partPath, doc] of context.parsedDocuments) {
+    context.textModifications.set(partPath, serializeXml(doc));
+  }
+
   context.textModifications.set(destinationSlidePath, serializeXml(destinationSlideDocument));
   context.textModifications.set('[Content_Types].xml', serializeXml(contentTypesDocument));
   const buffer = await buildZip(
@@ -224,12 +230,29 @@ function fallbackUuid(): string {
   });
 }
 
-async function copyShapeRelationships(
+function getOrParseRelationshipsDocument(
+  destinationRelationshipsPath: string,
+  context: PasteContext
+): XMLDocument {
+  const existing = context.parsedDocuments.get(destinationRelationshipsPath);
+  if (existing) return existing;
+
+  const xmlText =
+    context.textModifications.get(destinationRelationshipsPath) ??
+    context.destination.textFiles.get(destinationRelationshipsPath);
+  const doc = xmlText
+    ? parseXml(xmlText, destinationRelationshipsPath)
+    : createRelationshipsDocument();
+  context.parsedDocuments.set(destinationRelationshipsPath, doc);
+  return doc;
+}
+
+function copyShapeRelationships(
   sourceSlidePath: string,
   destinationSlidePath: string,
   clonedShape: Element,
   context: PasteContext
-): Promise<void> {
+): void {
   const sourceRelationshipsPath = getRelationshipsPath(sourceSlidePath);
   const sourceRelationshipsXml = context.source.textFiles.get(sourceRelationshipsPath);
   const relationshipAttributes = getRelationshipAttributes(clonedShape);
@@ -237,9 +260,7 @@ async function copyShapeRelationships(
 
   const sourceRelationships = parseXml(sourceRelationshipsXml, sourceRelationshipsPath);
   const destinationRelationshipsPath = getRelationshipsPath(destinationSlidePath);
-  const destinationRelationships = context.destination.textFiles.has(destinationRelationshipsPath)
-    ? parseXml(getRequiredTextFile(context.destination, destinationRelationshipsPath), destinationRelationshipsPath)
-    : createRelationshipsDocument();
+  const destinationRelationships = getOrParseRelationshipsDocument(destinationRelationshipsPath, context);
 
   for (const attribute of relationshipAttributes) {
     const sourceRelationship = findRelationship(sourceRelationships, attribute.value);
@@ -253,7 +274,7 @@ async function copyShapeRelationships(
     const target = clonedRelationship.getAttribute('Target');
     if (target && clonedRelationship.getAttribute('TargetMode') !== 'External') {
       const sourceTargetPath = resolvePartPath(sourceSlidePath, target);
-      const destinationTargetPath = await ensureRelatedPart(
+      const destinationTargetPath = ensureRelatedPart(
         sourceTargetPath,
         context,
         isChartRelationship(clonedRelationship)
@@ -263,8 +284,6 @@ async function copyShapeRelationships(
 
     destinationRelationships.documentElement.appendChild(clonedRelationship);
   }
-
-  context.textModifications.set(destinationRelationshipsPath, serializeXml(destinationRelationships));
 }
 
 function getRelationshipAttributes(element: Element): Attr[] {
@@ -300,11 +319,11 @@ function isChartRelationship(relationship: Element): boolean {
   return relationship.getAttribute('Type')?.endsWith('/chart') ?? false;
 }
 
-async function ensureRelatedPart(
+function ensureRelatedPart(
   sourcePartPath: string,
   context: PasteContext,
   forceClone: boolean
-): Promise<string> {
+): string {
   const cached = context.clonedParts.get(sourcePartPath);
   if (cached) return cached;
 
@@ -336,16 +355,16 @@ async function ensureRelatedPart(
       if (!target || relationship.getAttribute('TargetMode') === 'External') continue;
 
       const sourceTargetPath = resolvePartPath(sourcePartPath, target);
-      const destinationTargetPath = await ensureRelatedPart(
+      const destinationTargetPath = ensureRelatedPart(
         sourceTargetPath,
         context,
         shouldCloneDependency(sourcePartPath, sourceTargetPath)
       );
       relationship.setAttribute('Target', getRelativePartPath(destinationPartPath, destinationTargetPath));
     }
-    context.textModifications.set(
+    context.parsedDocuments.set(
       getRelationshipsPath(destinationPartPath),
-      serializeXml(relationships)
+      relationships
     );
   }