diff --git a/httomo/runner/task_runner.py b/httomo/runner/task_runner.py
index 06fe1ee19..d125d475d 100644
--- a/httomo/runner/task_runner.py
+++ b/httomo/runner/task_runner.py
@@ -121,7 +121,7 @@ def _execute_section(self, section: Section, section_index: int = 0):
             unit="block",
             ascii=True,
         )
-        for idx, (block, _) in enumerate(zip(splitter, progress)):
+        for idx, block in enumerate(progress):
             end_source = time.perf_counter_ns()
             if self.monitor is not None:
                 self.monitor.report_source_block(