diff --git a/tmt/base.py b/tmt/base.py
index 46e32448e7..3486af399d 100644
--- a/tmt/base.py
+++ b/tmt/base.py
@@ -89,7 +89,7 @@ def fmf_id(self):
 
         def run(command):
             """ Run command, return output """
-            result = subprocess.run(command.split(), capture_output=True)
+            result = subprocess.run(command.split(), stdout=subprocess.PIPE)
             return result.stdout.strip().decode("utf-8")
 
         fmf_id = {'name': self.name}
diff --git a/tmt/export.py b/tmt/export.py
index 878f9ff6d0..49a6c9dea1 100644
--- a/tmt/export.py
+++ b/tmt/export.py
@@ -165,9 +165,9 @@ def export_to_nitrate(test, create, general):
             echo(style(section + ': ', fg='green') + attribute.strip())
 
     # fmf identifer
-    fmf_id = test.fmf_id
-    struct_field.set('fmf', yaml.dump(fmf_id))
-    echo(style('fmf id:\n', fg='green') + yaml.dump(fmf_id).strip())
+    fmf_id = tmt.utils.dict_to_yaml(test.fmf_id)
+    struct_field.set('fmf', fmf_id)
+    echo(style('fmf id:\n', fg='green') + fmf_id.strip())
 
     # Warning
     if WARNING not in struct_field.header():