diff --git a/internal/proc.h b/internal/proc.h
index c6a9e38bfa..24a077ca6d 100644
--- a/internal/proc.h
+++ b/internal/proc.h
@@ -22,7 +22,6 @@ int rb_block_min_max_arity(int *max);
 VALUE rb_block_to_s(VALUE self, const struct rb_block *block, const char *additional_info);
 VALUE rb_callable_receiver(VALUE);
 
-VALUE rb_func_proc_new(rb_block_call_func_t func, VALUE val);
 VALUE rb_func_proc_dup(VALUE src_obj);
 VALUE rb_func_lambda_new(rb_block_call_func_t func, VALUE val, int min_argc, int max_argc);
 VALUE rb_iseq_location(const struct rb_iseq_struct *iseq);
diff --git a/proc.c b/proc.c
index 88e0fbebbb..29873923de 100644
--- a/proc.c
+++ b/proc.c
@@ -752,13 +752,6 @@ rb_vm_ifunc_new(rb_block_call_func_t func, const void *data, int min_argc, int m
     return ifunc;
 }
 
-VALUE
-rb_func_proc_new(rb_block_call_func_t func, VALUE val)
-{
-    struct vm_ifunc *ifunc = rb_vm_ifunc_proc_new(func, (void *)val);
-    return cfunc_proc_new(rb_cProc, (VALUE)ifunc);
-}
-
 VALUE
 rb_func_lambda_new(rb_block_call_func_t func, VALUE val, int min_argc, int max_argc)
 {