diff --git a/tljh/conda.py b/tljh/conda.py
index df9a027..ca849e8 100644
--- a/tljh/conda.py
+++ b/tljh/conda.py
@@ -98,7 +98,7 @@ def install_miniconda(installer_path, prefix):
     fix_permissions(prefix)
 
 
-def ensure_conda_packages(prefix, packages):
+def ensure_conda_packages(prefix, packages, force=False):
     """
     Ensure packages (from conda-forge) are installed in the conda prefix.
 
@@ -110,13 +110,16 @@ def ensure_conda_packages(prefix, packages):
         # fallback on conda if mamba is not present (e.g. for mamba to install itself)
         conda_executable = os.path.join(prefix, "bin", "conda")
 
+    cmd = [conda_executable, "install", "--yes"]
+
+    if force:
+        cmd += ["--force"]
+
     abspath = os.path.abspath(prefix)
 
     utils.run_subprocess(
-        [
-            conda_executable,
-            "install",
-            "-y",
+        cmd
+        + [
             "-c",
             "conda-forge",  # Make customizable if we ever need to
             "--prefix",
diff --git a/tljh/installer.py b/tljh/installer.py
index b65ddac..8c429ec 100644
--- a/tljh/installer.py
+++ b/tljh/installer.py
@@ -249,6 +249,8 @@ def ensure_user_environment(user_requirements_txt_file):
                 # we _could_ explicitly pin Python here,
                 # but conda already does this by default
                 cf_pkgs_to_upgrade,
+                # use force to avoid RemoveError: 'requests' is a dependency of conda
+                force=True,
             )
         pypi_pkgs_to_upgrade = list(set(to_upgrade) & {"pip"})
         if pypi_pkgs_to_upgrade: