diff --git a/mkhelper.mk.in b/mkhelper.mk.in
index cf37635..b66f21d 100644
--- a/mkhelper.mk.in
+++ b/mkhelper.mk.in
@@ -193,6 +193,7 @@ sanitize-mod-proxies:
 extra_f90.d: mkhelper.mk
 	$(silent_DEPGEN):;{ \
 	  echo 'src/program/main.o:| src/program/implicit_external.o'; \
+	  echo 'src/program/main.o:| src/modules/submo_test_submodule.o'; \
 	} >$@
 
 # Configure delayed bundled libraries:
diff --git a/mkhelper/depgen.py b/mkhelper/depgen.py
index e75b3de..ae34679 100755
--- a/mkhelper/depgen.py
+++ b/mkhelper/depgen.py
@@ -460,6 +460,9 @@ def module_declare_callback(module):
     def module_use_callback(module):
         required_modules.add(module)
 
+    def submodule_declare_callback(module, submodule):
+        required_modules.add(module)
+
     lc_debug_info = None
     pp_debug_info = None
     ftn_debug_info = None
@@ -478,6 +481,7 @@ def module_use_callback(module):
 
         ftn.include_callback = include_callback
         ftn.module_declare_callback = module_declare_callback
+        ftn.submodule_declare_callback = submodule_declare_callback
         ftn.module_use_callback = module_use_callback
 
         def debug_callback(line, msg):
diff --git a/mkhelper/depgen/fortran_parser.py b/mkhelper/depgen/fortran_parser.py
index fb642a8..6c6776f 100644
--- a/mkhelper/depgen/fortran_parser.py
+++ b/mkhelper/depgen/fortran_parser.py
@@ -46,6 +46,8 @@ class FortranParser:
     _re_module_declare = re.compile(
         r"^\s*module\s+(?!(?:procedure|subroutine|function)\s)(\w+)", re.I
     )
+    _re_submodule_declare = re.compile(
+        r"^\s*submodule\s+\(\s*(\w+)\s*\)\s+(\w+)", re.I)
     _re_module_use = re.compile(
         r"^\s*use(?:\s+|(?:\s*,\s*((?:non_)?intrinsic))?\s*::\s*)(\w+)", re.I
     )
@@ -73,6 +75,7 @@ def __init__(
         # Callbacks:
         self.include_callback = None
         self.module_declare_callback = None
+        self.submodule_declare_callback = None
         self.module_use_callback = None
         self.debug_callback = None
 
@@ -124,6 +127,19 @@ def parse(self, stream):
                             )
                         continue
 
+                    # submodule declared
+                    match = FortranParser._re_submodule_declare.match(line)
+                    if match:
+                        module_name = match.group(1).lower()
+                        submodule_name = match.group(2).lower()
+                        if self.submodule_declare_callback:
+                            self.submodule_declare_callback(module_name, submodule_name)
+                        if self.debug_callback:
+                            self.debug_callback(
+                                line, "declared submodule '%s' of module '%s'" % (submodule_name, module_name)
+                            )
+                        continue
+
                     # module used
                     match = FortranParser._re_module_use.match(line)
                     if match:
diff --git a/src/modules/mo_test_submodule.f90 b/src/modules/mo_test_submodule.f90
new file mode 100644
index 0000000..11ae05f
--- /dev/null
+++ b/src/modules/mo_test_submodule.f90
@@ -0,0 +1,18 @@
+module mo_test_submodule
+  implicit none
+  public
+
+  interface
+    module subroutine print_hello_subroutine()
+    end subroutine print_hello_subroutine
+
+    module function print_hello_function()
+      integer :: print_hello_function
+    end function print_hello_function
+  end interface
+
+  contains
+    subroutine print_hello()
+      print *, "Hello from submodule test (parent module)."
+    end subroutine print_hello
+end module mo_test_submodule
diff --git a/src/modules/submo_test_submodule.f90 b/src/modules/submo_test_submodule.f90
new file mode 100644
index 0000000..72c8f0a
--- /dev/null
+++ b/src/modules/submo_test_submodule.f90
@@ -0,0 +1,14 @@
+submodule (mo_test_submodule) submo_test_submodule
+  implicit none
+
+contains
+  module subroutine print_hello_subroutine()
+    print *, "Hello from submodule test (submodule subroutine)."
+  end subroutine print_hello_subroutine
+
+  module function print_hello_function()
+    integer :: print_hello_function
+    print_hello_function = 0
+    print *, "Hello from submodule test (submodule function)."
+  end function print_hello_function
+end submodule submo_test_submodule
diff --git a/src/program/main.f90 b/src/program/main.f90
index 0ba1c2b..7104dfb 100644
--- a/src/program/main.f90
+++ b/src/program/main.f90
@@ -3,6 +3,10 @@
 program main
 
   use mo_mkhelper, only: print_mkhelper_hello => print_hello
+  use mo_test_submodule, only: &
+  &  print_test_submodule_parent => print_hello, &
+  &  print_test_submodule_subroutine => print_hello_subroutine, &
+  &  print_test_submodule_function => print_hello_function
   use mo_threaded_hello, only: print_threaded_hello => print_hello
   use mo_delayed, only: print_delayed_hello => print_hello
   use mo_cmake_based, only: print_cmake_based_hello => print_hello
@@ -82,6 +86,10 @@ program main
 
   call print_mkhelper_hello()
 
+  call print_test_submodule_parent()
+  call print_test_submodule_subroutine()
+  retval = print_test_submodule_function()
+
   print *, "Running threaded bundled library..."
   retval = print_threaded_hello()
   if (retval .ne. 0) stop 2