diff --git a/sources/mesh.F90 b/sources/mesh.F90
index e7908cf..c7e3a50 100644
--- a/sources/mesh.F90
+++ b/sources/mesh.F90
@@ -28,18 +28,12 @@
 module mesh
 
 #ifdef PROFILE
-! import external subroutines
-!
   use timers, only : set_timer, start_timer, stop_timer
 #endif /* PROFILE */
 
-! module variables are not implicit by default
-!
   implicit none
 
 #ifdef PROFILE
-! timer indices
-!
   integer            , save :: imi, ims, img, imu, ima, imp, imr
 #endif /* PROFILE */
 
@@ -51,9 +45,22 @@ module mesh
     end subroutine
   end interface
 
+! interfaces for the problem setup
+!
+  abstract interface
+    subroutine setup_problem_iface(pdata)
+      use blocks, only : block_data
+      type(block_data), pointer, intent(inout) :: pdata
+    end subroutine
+  end interface
+
 ! pointer to the problem domain setup subroutine
 !
-  procedure(setup_domain_iface), pointer, save :: setup_domain => null()
+  procedure(setup_domain_iface) , pointer, save :: setup_domain => null()
+
+! pointer to the problem initial setup subroutine
+!
+  procedure(setup_problem_iface), pointer, save :: setup_problem => null()
 
 ! the handler of the mesh statistics file
 !
@@ -72,6 +79,7 @@ module mesh
   public :: initialize_mesh, finalize_mesh, print_mesh
   public :: generate_mesh, update_mesh
   public :: redistribute_blocks, store_mesh_stats
+  public :: setup_problem
 
 !- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 !
@@ -230,6 +238,8 @@ module mesh
 
     status = 0
 
+    nullify(setup_problem)
+
     if (master) close(funit)
 
     call finalize_refinement(status)
@@ -301,7 +311,6 @@ module mesh
     use helpers        , only : print_section
     use iso_fortran_env, only : error_unit
     use mpitools       , only : master, nproc, nprocs, npmax, nodes, lprocs
-    use problems       , only : setup_problem
     use refinement     , only : check_refinement_criterion
 
     implicit none
diff --git a/sources/problems.F90 b/sources/problems.F90
index 66317f5..9e032f0 100644
--- a/sources/problems.F90
+++ b/sources/problems.F90
@@ -32,46 +32,20 @@
 module problems
 
 #ifdef PROFILE
-! include external procedures
-!
   use timers, only : set_timer, start_timer, stop_timer
 #endif /* PROFILE */
 
-! module variables are not implicit by default
-!
   implicit none
 
 #ifdef PROFILE
-! timer indices
-!
   integer, save :: imi, imu
 #endif /* PROFILE */
 
-! problem name
-!
   character(len=64), save :: problem_name = "none"
 
-! interfaces for procedure pointers
-!
-  abstract interface
-    subroutine setup_problem_iface(pdata)
-      use blocks, only : block_data
-      type(block_data), pointer, intent(inout) :: pdata
-    end subroutine
-  end interface
-
-! pointer to the problem setup subroutine
-!
-  procedure(setup_problem_iface), pointer, save :: setup_problem => null()
-
-! by default everything is private
-!
   private
 
-! declare public subroutines
-!
   public :: initialize_problems, finalize_problems
-  public :: setup_problem
   public :: problem_name
 
 !- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -102,6 +76,7 @@ module problems
 !
   subroutine initialize_problems(problem, rcount, verbose, status)
 
+    use mesh        , only : setup_problem
     use parameters  , only : get_parameter
     use user_problem, only : initialize_user_problem, setup_user_problem
 
@@ -111,7 +86,7 @@ module problems
     integer          , intent(in)  :: rcount
     logical          , intent(in)  :: verbose
     integer          , intent(out) :: status
-!
+
 !-------------------------------------------------------------------------------
 !
 #ifdef PROFILE
@@ -186,7 +161,7 @@ module problems
     implicit none
 
     integer, intent(out) :: status
-!
+
 !-------------------------------------------------------------------------------
 !
 #ifdef PROFILE
@@ -195,8 +170,6 @@ module problems
 
     status = 0
 
-    nullify(setup_problem)
-
     call finalize_user_problem(status)
 
 #ifdef PROFILE