diff --git a/tests/ert/ui_tests/cli/analysis/conftest.py b/tests/ert/ui_tests/cli/analysis/conftest.py
new file mode 100644
index 00000000000..bdbcd5e0197
--- /dev/null
+++ b/tests/ert/ui_tests/cli/analysis/conftest.py
@@ -0,0 +1,24 @@
+import os
+
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def reduce_omp_num_threads_count():
+    multithreading_env_variables = [
+        ["OMP_NUM_THREADS", "1"],  # OpenMP
+        ["MKL_NUM_THREADS", "1"],  # Intel Math Kernel Library
+        ["NUMEXPR_NUM_THREADS", "1"],  # NumExpr library in Python
+    ]
+    for option in multithreading_env_variables:
+        env_var_name = option[0]
+        option[1], os.environ[env_var_name] = os.environ.get(env_var_name), option[1]
+
+    yield
+
+    for option in multithreading_env_variables:
+        env_var_name = option[0]
+        if option[1] is None:
+            del os.environ[env_var_name]
+        else:
+            os.environ[env_var_name] = option[1]