diff --git a/core/commands/branch.py b/core/commands/branch.py
index f8ec471e8..88e815b88 100644
--- a/core/commands/branch.py
+++ b/core/commands/branch.py
@@ -39,8 +39,8 @@
 """
 
 EXTRACT_COMMIT = re.compile(r"\(was (.+)\)")
-NOT_MERGED_WARNING = re.compile(r"The branch.*is not fully merged\.")
-CANT_DELETE_CURRENT_BRANCH = re.compile(r"Cannot delete branch .+ checked out at ")
+NOT_MERGED_WARNING = re.compile(r"the branch.*is not fully merged\.", re.I)
+CANT_DELETE_USED_BRANCH = re.compile(r"cannot delete branch .+ (checked out|used by worktree) at ", re.I)
 
 
 def just(value):
@@ -172,7 +172,10 @@ def run(self, branch, force=False):
                 if NOT_MERGED_WARNING.search(e.stderr):
                     self.offer_force_deletion(branch)
                     return
-                if CANT_DELETE_CURRENT_BRANCH.search(e.stderr):
+                if (
+                    CANT_DELETE_USED_BRANCH.search(e.stderr)
+                    and branch == self.get_current_branch_name()
+                ):
                     self.offer_detaching_head(branch)
                     return
                 e.show_error_panel()