diff --git a/core-modules/001QubesResizableVm.py b/core-modules/001QubesResizableVm.py
index 5e898b40..f50ead70 100644
--- a/core-modules/001QubesResizableVm.py
+++ b/core-modules/001QubesResizableVm.py
@@ -36,7 +36,7 @@ from time import sleep
 
 class QubesResizableVm(QubesVm):
 
-    def resize_root_img(self, size):
+    def resize_root_img(self, size, allow_start=False):
         if self.template:
             raise QubesException("Cannot resize root.img of template-based VM"
                                  ". Resize the root.img of the template "
@@ -57,8 +57,14 @@ class QubesResizableVm(QubesVm):
 
 class QubesResizableVmWithResize2fs(QubesResizableVm):
 
-    def resize_root_img(self, size):
-        super(QubesResizableVmWithResize2fs, self).resize_root_img(size)
+    def resize_root_img(self, size, allow_start=False):
+        super(QubesResizableVmWithResize2fs, self).\
+            resize_root_img(size, allow_start=allow_start)
+        if not allow_start:
+            raise QubesException("VM start required to complete the "
+                                 "operation, but not allowed. Either run the "
+                                 "operation again allowing VM start this "
+                                 "time, or run resize2fs in the VM manually.")
         self.start(start_guid=False)
         self.run("resize2fs /dev/mapper/dmroot", user="root", wait=True,
                  gui=False)
diff --git a/qvm-tools/qvm-grow-root b/qvm-tools/qvm-grow-root
index 93c55bb2..5e650ab7 100755
--- a/qvm-tools/qvm-grow-root
+++ b/qvm-tools/qvm-grow-root
@@ -34,6 +34,10 @@ def main():
     usage = "usage: %prog <vm-name> <size>"
     parser = OptionParser (usage)
 
+    parser.add_option("--allow-start", action="store_true",
+                      dest="allow_start", default=False,
+                      help="Allow VM to be started to complete the operation")
+
     (options, args) = parser.parse_args ()
     if (len (args) != 2):
         parser.error ("You must specify VM name and new size!")
@@ -57,7 +61,7 @@ def main():
         exit(1)
 
     try:
-        vm.resize_root_img(size_bytes)
+        vm.resize_root_img(size_bytes, allow_start=options.allow_start)
     except (IOError, OSError, QubesException) as err:
         print >> sys.stderr, "ERROR: {0}".format(err)
         exit (1)
diff --git a/tests/vm_qrexec_gui.py b/tests/vm_qrexec_gui.py
index c64da4d4..aa4e3da4 100644
--- a/tests/vm_qrexec_gui.py
+++ b/tests/vm_qrexec_gui.py
@@ -731,7 +731,9 @@ class TC_05_StandaloneVM(qubes.tests.SystemTestsMixin, qubes.tests.QubesTestCase
                                source_template=self.qc.get_default_template())
         self.qc.save()
         self.qc.unlock_db()
-        testvm1.resize_root_img(20*1024**3)
+        with self.assertRaises(QubesException):
+            testvm1.resize_root_img(20*1024**3)
+        testvm1.resize_root_img(20*1024**3, allow_start=True)
         timeout = 60
         while testvm1.is_running():
             time.sleep(1)