diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
index 92ff283013e..d0da2300ba9 100644
--- a/gcc/cp/constraint.cc
+++ b/gcc/cp/constraint.cc
@@ -1075,6 +1075,19 @@ associate_classtype_constraints (tree type)
 	 original declaration.  */
       if (tree orig_ci = get_constraints (decl))
         {
+	  if (int extra_levels = (TMPL_PARMS_DEPTH (current_template_parms)
+				  - TMPL_ARGS_DEPTH (TYPE_TI_ARGS (type))))
+	    {
+	      /* If there is a discrepancy between the current template depth
+		 and the template depth of the original declaration, then we
+		 must be redeclaring a class template as part of a friend
+		 declaration within another class template.  Before matching
+		 constraints, we need to reduce the template parameter level
+		 within the current constraints via substitution.  */
+	      tree outer_gtargs = template_parms_to_args (current_template_parms);
+	      TREE_VEC_LENGTH (outer_gtargs) = extra_levels;
+	      ci = tsubst_constraint_info (ci, outer_gtargs, tf_none, NULL_TREE);
+	    }
           if (!equivalent_constraints (ci, orig_ci))
             {
 	      error ("%qT does not match original declaration", type);
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index c07a48f1261..cdf6a3eeaf3 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -11213,6 +11213,16 @@ tsubst_friend_class (tree friend_tmpl, tree args)
 	  DECL_ANTICIPATED (tmpl)
 	    = DECL_ANTICIPATED (DECL_TEMPLATE_RESULT (tmpl)) = true;
 
+	  /* Substitute into and set the constraints on the new declaration.  */
+	  if (tree ci = get_constraints (friend_tmpl))
+	    {
+	      ++processing_template_decl;
+	      ci = tsubst_constraint_info (ci, args, tf_warning_or_error,
+					   DECL_FRIEND_CONTEXT (friend_tmpl));
+	      --processing_template_decl;
+	      set_constraints (tmpl, ci);
+	    }
+
 	  /* Inject this template into the enclosing namspace scope.  */
 	  tmpl = pushdecl_namespace_level (tmpl, true);
 	}
diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-friend6.C b/gcc/testsuite/g++.dg/cpp2a/concepts-friend6.C
new file mode 100644
index 00000000000..11e8313f0ac
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/concepts-friend6.C
@@ -0,0 +1,19 @@
+// PR c++/93467
+// { dg-do compile { target c++20 } }
+
+template<bool B> requires B
+  class C;
+
+template<typename>
+class S1
+{
+  template<bool B> requires B
+    friend class ::C;
+};
+
+template<typename>
+class S2
+{
+  template<bool B> requires (!B)
+    friend class ::C; // { dg-error "does not match original declaration" }
+};
diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-friend7.C b/gcc/testsuite/g++.dg/cpp2a/concepts-friend7.C
new file mode 100644
index 00000000000..4481b5c4af4
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/concepts-friend7.C
@@ -0,0 +1,18 @@
+// PR c++/93467
+// { dg-do compile { target c++20 } }
+
+template<typename T> concept True = true;
+
+template<typename U>
+struct S1 {
+    template<True T> friend struct S2; // friend declaration for S2
+};
+
+S1<int> s; // instantiate S1
+
+template<True T> struct S2; // another declaration for S2
+
+template<typename U>
+struct S3 {
+    template<True T> friend struct ::S2; // a third declaration for S2
+};