diff --git a/src/ansys/edb/core/inner/messages.py b/src/ansys/edb/core/inner/messages.py
index 596fe89330..669094b17e 100644
--- a/src/ansys/edb/core/inner/messages.py
+++ b/src/ansys/edb/core/inner/messages.py
@@ -958,6 +958,7 @@ def mesh_operation_message(mesh_op):
         refine_inside=mesh_op.refine_inside,
         mesh_region=mesh_op.mesh_region,
         net_layer_info=[_mesh_op_net_layer_message(*nl) for nl in mesh_op.net_layer_info],
+        solve_inside=mesh_op.solve_inside,
     )
     if isinstance(mesh_op, LengthMeshOperation):
         mesh_op_msg.length_mesh_op.CopyFrom(_length_mesh_operation_message(mesh_op))
diff --git a/src/ansys/edb/core/inner/parser.py b/src/ansys/edb/core/inner/parser.py
index 16432c0a0a..0102e3bf3e 100644
--- a/src/ansys/edb/core/inner/parser.py
+++ b/src/ansys/edb/core/inner/parser.py
@@ -473,6 +473,7 @@ def _to_mesh_op(message):
     mesh_op.enabled = message.enabled
     mesh_op.mesh_region = message.mesh_region
     mesh_op.refine_inside = message.refine_inside
+    mesh_op.solve_inside = message.solve_inside
     for nli in message.net_layer_info:
         mesh_op.net_layer_info.append((nli.net, nli.layer, nli.is_sheet))
     return mesh_op
diff --git a/src/ansys/edb/core/simulation_setup/mesh_operation.py b/src/ansys/edb/core/simulation_setup/mesh_operation.py
index 89dcdb8962..e4d65277ad 100644
--- a/src/ansys/edb/core/simulation_setup/mesh_operation.py
+++ b/src/ansys/edb/core/simulation_setup/mesh_operation.py
@@ -17,6 +17,8 @@ class MeshOperation:
         Whether to refine inside.
     mesh_region : str, default: ""
         Mesh region.
+    solve_inside : bool, default: False
+        Whether to solve inside.
     """
 
     def __init__(
@@ -26,6 +28,7 @@ def __init__(
         enabled=True,
         refine_inside=False,
         mesh_region="",
+        solve_inside=False,
     ):
         """Create a mesh operation."""
         self._name = name
@@ -33,6 +36,7 @@ def __init__(
         self._enabled = enabled
         self._refine_inside = refine_inside
         self._mesh_region = mesh_region
+        self._solve_inside = solve_inside
 
     @property
     def name(self):
@@ -83,6 +87,15 @@ def mesh_region(self):
     def mesh_region(self, mesh_region):
         self._mesh_region = mesh_region
 
+    @property
+    def solve_inside(self):
+        """:obj:`bool`: Flag indicating if solve inside is enabled."""
+        return self._solve_inside
+
+    @solve_inside.setter
+    def solve_inside(self, solve_inside):
+        self._solve_inside = solve_inside
+
 
 class SkinDepthMeshOperation(MeshOperation):
     """Represents a skin depth mesh operation.
@@ -100,6 +113,8 @@ class SkinDepthMeshOperation(MeshOperation):
         Whether to refine inside.
     mesh_region : str, default: ""
         Mesh region.
+    solve_inside : bool, default: False
+        Whether to solve inside.
     skin_depth : str, default: "1um"
         Skin depth.`.
     surface_triangle_length : str, default: "1mm"
@@ -119,6 +134,7 @@ def __init__(
         enabled=True,
         refine_inside=False,
         mesh_region="",
+        solve_inside=False,
         skin_depth="1um",
         surface_triangle_length="1mm",
         num_layers="2",
@@ -126,7 +142,7 @@ def __init__(
         restrict_max_elements=False,
     ):
         """Create a skin depth mesh operation."""
-        super().__init__(name, net_layer_info, enabled, refine_inside, mesh_region)
+        super().__init__(name, net_layer_info, enabled, refine_inside, mesh_region, solve_inside)
         self._skin_depth = skin_depth
         self._surface_triangle_length = surface_triangle_length
         self._num_layers = num_layers
@@ -195,6 +211,8 @@ class LengthMeshOperation(MeshOperation):
         Whether to refine inside.
     mesh_region : str, default: ""
         Mesh region.
+    solve_inside : bool, default: False
+        Whether to solve inside.
     max_length : str, default: "1mm"
         maximum length of the mesh elements.
     restrict_max_length : str, default: True
@@ -212,13 +230,14 @@ def __init__(
         enabled=True,
         refine_inside=False,
         mesh_region="",
+        solve_inside=False,
         max_length="1mm",
         restrict_max_length=True,
         max_elements="1000",
         restrict_max_elements=False,
     ):
         """Initialize an instance of a skin depth mesh operation."""
-        super().__init__(name, net_layer_info, enabled, refine_inside, mesh_region)
+        super().__init__(name, net_layer_info, enabled, refine_inside, mesh_region, solve_inside)
         self._max_length = max_length
         self._restrict_max_length = restrict_max_length
         self._max_elements = max_elements