diff --git a/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py b/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py
index 5eb502ce99..0274521deb 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py
@@ -323,12 +323,16 @@ class Usecase:
 
         element_identity = element.wrapped_data.identity()
 
-        # check if inverse element were created before
-        if self.reuse_identities.get(element_identity) is not None:
-            return
-
-        new = self.file.create_entity(element.is_a())
-        self.reuse_identities[element_identity] = new
+        # Check if inverse element was created before.
+        # Still need to recreate it again - e.g. it could be some rel
+        # that now needs it's RelatingObjects to be extended by the current asset.
+        if (new := self.reuse_identities.get(element_identity)) is not None:
+            # Currently known cases requiring attributes reassignment are rels.
+            if not new.is_a("IfcRelationship"):
+                return
+        else:
+            new = self.file.create_entity(element.is_a())
+            self.reuse_identities[element_identity] = new
 
         for i, attribute in enumerate(element):
             new_attribute = None
@@ -346,11 +350,21 @@ class Usecase:
                 new[i] = new_attribute
 
     def is_another_asset(self, element: ifcopenshell.entity_instance) -> bool:
+        """Is IFC entity from inverse attribute is another asset to append that should be skipped."""
+
+        def by_guid(guid: str) -> Union[ifcopenshell.entity_instance, None]:
+            try:
+                return self.file.by_guid(guid)
+            except RuntimeError:
+                return None
+
         if element == self.settings["element"]:
             return False
         elif element.is_a("IfcFeatureElement"):
             # Feature elements match the target class but aren't considered "assets"
             return False
+        elif element.is_a("IfcRoot") and by_guid(element.GlobalId) is not None:
+            return False
         elif element.is_a(self.target_class):
             return True
         elif self.target_class == "IfcProduct" and element.is_a("IfcTypeProduct"):
diff --git a/src/ifcopenshell-python/test/api/project/test_append_asset.py b/src/ifcopenshell-python/test/api/project/test_append_asset.py
index e467bd4937..224d2f9d1b 100644
--- a/src/ifcopenshell-python/test/api/project/test_append_asset.py
+++ b/src/ifcopenshell-python/test/api/project/test_append_asset.py
@@ -433,6 +433,24 @@ class TestAppendAssetIFC2X3(test.bootstrap.IFC2X3):
         del shading_colour_info["id"], shading_colour_info["type"]
         assert shading_colour_info == shading_attrs["SurfaceColour"]
 
+    def test_update_rels_appending_subsequent_assets(self):
+        library = ifcopenshell.api.project.create_file(version=self.file.schema)
+        element1 = ifcopenshell.api.root.create_entity(library, ifc_class="IfcWall")
+        pset = ifcopenshell.api.pset.add_pset(library, product=element1, name="Test")
+        element2 = ifcopenshell.api.root.create_entity(library, ifc_class="IfcWall")
+        ifcopenshell.api.pset.assign_pset(library, pset=pset, products=[element2])
+
+        reuse_identities = {}
+        element1_ = ifcopenshell.api.project.append_asset(
+            self.file, library, element1, reuse_identities=reuse_identities
+        )
+        element2_ = ifcopenshell.api.project.append_asset(
+            self.file, library, element2, reuse_identities=reuse_identities
+        )
+        pset_data = ifcopenshell.util.element.get_psets(element1_)
+        assert "Test" in pset_data
+        assert ifcopenshell.util.element.get_psets(element2_) == pset_data
+
 
 class TestAppendAssetIFC4(test.bootstrap.IFC4, TestAppendAssetIFC2X3):
     # NOTE: breaks in IFC2X3 since IfcProfileDef doesn't have "HasProperties" inverse in ifc2x3