diff --git a/src/MeshKernelNET/Api/IMeshKernelApi.cs b/src/MeshKernelNET/Api/IMeshKernelApi.cs
index d4c0013..1f28904 100644
--- a/src/MeshKernelNET/Api/IMeshKernelApi.cs
+++ b/src/MeshKernelNET/Api/IMeshKernelApi.cs
@@ -1013,9 +1013,10 @@ int Mesh2dComputeOrthogonalization(int meshKernelId,
         /// </summary>
         /// <param name="meshKernelId">Id of the mesh state pertaining to the current domain</param>
         /// <param name="disposableMesh2D">The mesh to merge to the current domain</param>
+        /// <param name="geometryListPolygon">Input polygon to define the region of the operation. Can be empty -> whole meshes are considered</param>
         /// <param name="searchFraction">Fraction of the shortest edge (along an edge to be connected) to use when determining neighbour edge closeness</param>
         /// <returns>Error code</returns>
-        int Mesh2dMergeAndConnectMeshes(int meshKernelId, in DisposableMesh2D disposableMesh2D, double searchFraction);
+        int Mesh2dMergeAndConnectMeshes(int meshKernelId, in DisposableMesh2D disposableMesh2D,in DisposableGeometryList geometryListPolygon, double searchFraction);
 
         /// <summary>
         /// Converts the projection of a mesh2d
diff --git a/src/MeshKernelNET/Api/MeshKernelApi.cs b/src/MeshKernelNET/Api/MeshKernelApi.cs
index 35a5a13..8f203dc 100644
--- a/src/MeshKernelNET/Api/MeshKernelApi.cs
+++ b/src/MeshKernelNET/Api/MeshKernelApi.cs
@@ -943,18 +943,22 @@ public int Mesh2dComputeOrthogonalization(int meshKernelId,
         public int Mesh2dMergeMeshes(int meshKernelId, 
                                      in DisposableMesh2D disposableMesh2D)
         {
+            GeometryListNative geometryListPolygonNative = new GeometryListNative { numberOfCoordinates = 0 };
             Mesh2DNative mesh2D = disposableMesh2D.CreateNativeObject();
             return MeshKernelDll.Mesh2dConnectMeshes(meshKernelId,
                                                      ref mesh2D,
+                                                     geometryListPolygonNative,
                                                      0.0, 
                                                      false);
         }
 
-        public int Mesh2dMergeAndConnectMeshes(int meshKernelId, in DisposableMesh2D disposableMesh2D, double searchFraction)
+        public int Mesh2dMergeAndConnectMeshes(int meshKernelId, in DisposableMesh2D disposableMesh2D, in DisposableGeometryList geometryListPolygon, double searchFraction)
         {
             Mesh2DNative mesh2D = disposableMesh2D.CreateNativeObject();
+            GeometryListNative geometryListPolygonNative = geometryListPolygon?.CreateNativeObject() ?? new GeometryListNative { numberOfCoordinates = 0 };
             return MeshKernelDll.Mesh2dConnectMeshes(meshKernelId,
                                                      ref mesh2D,
+                                                     geometryListPolygonNative,
                                                      searchFraction,
                                                      true);
         }
diff --git a/src/MeshKernelNET/Native/MeshKernelDll.cs b/src/MeshKernelNET/Native/MeshKernelDll.cs
index 8171cbc..28a25f4 100644
--- a/src/MeshKernelNET/Native/MeshKernelDll.cs
+++ b/src/MeshKernelNET/Native/MeshKernelDll.cs
@@ -1155,11 +1155,16 @@ internal static extern int Mesh2dComputeOrthogonalization([In] int meshKernelId,
         /// </summary>
         /// <param name="meshKernelId">Id of the mesh state pertaining to the current domain</param>
         /// <param name="mesh2DNative">The mesh to merge to the current domain</param>
+        /// <param name="geometryListNativePolygon">The polygon where to connect the meshes </param>
         /// <param name="searchFraction">Fraction of the shortest edge (along an edge to be connected) to use when determining neighbour edge closeness</param>
         /// <param name="connect">Boolean value indicating if the two meshes should be connected using triangles</param>
         /// <returns>Error code</returns>
         [DllImport(MeshKernelDllName, EntryPoint = "mkernel_mesh2d_connect_meshes", CallingConvention = CallingConvention.Cdecl)]
-        internal static extern int Mesh2dConnectMeshes([In] int meshKernelId, [In] ref Mesh2DNative mesh2DNative, [In] double searchFraction, [In] bool connect);
+        internal static extern int Mesh2dConnectMeshes([In] int meshKernelId, 
+                                                        [In] ref Mesh2DNative mesh2DNative,
+                                                        [In] GeometryListNative geometryListNativePolygon,
+                                                        [In] double searchFraction,
+                                                        [In] bool connect);
 
         /// <summary>
         /// Converts the projection of a mesh2d
diff --git a/test/MeshKernelNETTest/Api/MeshKernelTest.cs b/test/MeshKernelNETTest/Api/MeshKernelTest.cs
index 91121db..cfc51f7 100644
--- a/test/MeshKernelNETTest/Api/MeshKernelTest.cs
+++ b/test/MeshKernelNETTest/Api/MeshKernelTest.cs
@@ -2277,6 +2277,7 @@ public void Mesh2dMergeMeshesThroughApi()
         public void Mesh2dMergeAndConnectMeshesThroughApi()
         {
             // Setup
+            using(var disposableGeometryList = new DisposableGeometryList())
             using (DisposableMesh2D firstMesh = CreateMesh2D(3, 3, 1, 1))
             using (DisposableMesh2D secondMesh = CreateMesh2D(6, 6, 0.5, 0.5, 1.0))
             using (var api = new MeshKernelApi())
@@ -2292,7 +2293,7 @@ public void Mesh2dMergeAndConnectMeshesThroughApi()
 
                     // Execute
                     const double searchFraction = 0.4;
-                    var result = api.Mesh2dMergeAndConnectMeshes(id, secondMesh, searchFraction);
+                    var result = api.Mesh2dMergeAndConnectMeshes(id, secondMesh,disposableGeometryList, searchFraction);
 
                     // Assert
                     Assert.That(result, Is.EqualTo(0));