diff --git a/cate/util/web/jsonrpcmonitor.py b/cate/util/web/jsonrpcmonitor.py
index 5911b056d..627dc9e2f 100644
--- a/cate/util/web/jsonrpcmonitor.py
+++ b/cate/util/web/jsonrpcmonitor.py
@@ -86,7 +86,7 @@ def start(self, label: str, total_work: float = None):
         self.label = label
         self.total = total_work
         self.worked = 0.0 if total_work else None
-        self._write_progress(message='Started')
+        self._write_progress()
         # first progress method should always be sent
         self.last_time = None
 
@@ -98,7 +98,7 @@ def progress(self, work: float = None, msg: str = None):
 
     def done(self):
         self.worked = self.total
-        self._write_progress(message='Done')
+        self._write_progress()
 
     def cancel(self):
         self._cancelled = True
diff --git a/cate/webapi/wsmanag.py b/cate/webapi/wsmanag.py
index 8216ccd11..b27531eb8 100644
--- a/cate/webapi/wsmanag.py
+++ b/cate/webapi/wsmanag.py
@@ -24,9 +24,10 @@
 import json
 import urllib.parse
 import urllib.request
-from tornado import gen, ioloop, websocket
 from typing import List
 
+from tornado import gen, ioloop, websocket
+
 from cate.conf.defaults import WEBAPI_WORKSPACE_TIMEOUT, WEBAPI_RESOURCE_TIMEOUT, WEBAPI_PLOT_TIMEOUT
 from cate.core.workspace import Workspace, WorkspaceError, OpKwArgs
 from cate.core.wsmanag import WorkspaceManager
@@ -248,26 +249,36 @@ def _connect(self):
     @gen.coroutine
     def _invoke_method(self):
         self.ws.write_message(self.json_rpc_request)
-        work_reported = 0
+        work_reported = None
+        started = False
         while True:
             response = yield self.ws.read_message()
             json_response = json.loads(response)
-            if 'progress' in json_response and self.monitor:
-                progress = json_response['progress']
-                if 'message' in progress:
-                    message = progress['message']
-                    if message == 'Started':
-                        total = progress.get('total', 100)
-                        label = progress.get('label', '')
-                        self.monitor.start(label, total)
-                    elif message == 'Done':
-                        self.monitor.done()
-                    else:
-                        worked = progress.get('worked', 0)
-                        msg = progress.get('message', '')
-                        self.monitor.progress(worked - work_reported, msg)
-                        work_reported = worked
+            if 'progress' in json_response:
+                if self.monitor:
+                    progress = json_response['progress']
+                    total = progress.get('total')
+                    label = progress.get('label')
+                    worked = progress.get('worked')
+                    msg = progress.get('message')
+
+                    if not started:
+                        if total is not None or total is not None:
+                            self.monitor.start(label, total_work=total)
+                            started = True
+
+                    if started:
+                        if worked:
+                            if work_reported is None:
+                                work_reported = 0.0
+                            work = worked - work_reported
+                            work_reported = worked
+                        else:
+                            work = None
+                        self.monitor.progress(work=work, msg=msg)
             else:
+                if self.monitor and started:
+                    self.monitor.done()
                 return response
 
     def _format_rpc_request(self, method, params):
diff --git a/test/core/test_wsmanag.py b/test/core/test_wsmanag.py
index 1604a57e5..7ae9c3bf3 100644
--- a/test/core/test_wsmanag.py
+++ b/test/core/test_wsmanag.py
@@ -138,9 +138,9 @@ def test_resource_progress(self):
             ('progress', 1.0, 'Step 7 of 10 doing nothing', 70),
             ('progress', 1.0, 'Step 8 of 10 doing nothing', 80),
             ('progress', 1.0, 'Step 9 of 10 doing nothing', 90),
-            ('progress', 1.0, 'Step 10 of 10 doing nothing', 100)
-        ], rm.records[:11])
-        # in ws case 'done' is not transmitted
+            ('progress', 1.0, 'Step 10 of 10 doing nothing', 100),
+            ('done',)
+        ], rm.records)
         self.del_base_dir(base_dir)
 
     def test_session(self):