diff --git a/config/m4/ucx.m4 b/config/m4/ucx.m4
index 35bb55f9bd..97fd547881 100644
--- a/config/m4/ucx.m4
+++ b/config/m4/ucx.m4
@@ -119,6 +119,11 @@ AS_IF([test "x$ucx_checked" != "xyes"],[
                 [],
                 [#include <ucs/memory/rcache.h>])
 
+            AC_CHECK_MEMBER(ucs_rcache_ops_t.merge,
+                [AC_DEFINE([UCS_HAVE_RCACHE_MERGE_CB], [1], [flags for ucs_rcache_ops_t])],
+                [],
+                [#include <ucs/memory/rcache.h>])
+
             AC_DEFINE([HAVE_UCX], 1, [Enable UCX support])
 
             AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <ucs/config/parser.h>
diff --git a/src/components/tl/mlx5/mcast/tl_mlx5_mcast_rcache.c b/src/components/tl/mlx5/mcast/tl_mlx5_mcast_rcache.c
index 47f73e485b..67d1202c4f 100644
--- a/src/components/tl/mlx5/mcast/tl_mlx5_mcast_rcache.c
+++ b/src/components/tl/mlx5/mcast/tl_mlx5_mcast_rcache.c
@@ -130,7 +130,10 @@ void ucc_tl_mlx5_mcast_mem_deregister(ucc_tl_mlx5_mcast_coll_context_t *ctx,
 static ucc_rcache_ops_t ucc_tl_mlx5_rcache_ops = {
     .mem_reg     = ucc_tl_mlx5_mcast_rcache_mem_reg_cb,
     .mem_dereg   = ucc_tl_mlx5_mcast_rcache_mem_dereg_cb,
-    .dump_region = ucc_tl_mlx5_mcast_rcache_dump_region_cb
+    .dump_region = ucc_tl_mlx5_mcast_rcache_dump_region_cb,
+#ifdef UCS_HAVE_RCACHE_MERGE_CB
+    .merge       = ucc_rcache_merge_cb_empty
+#endif
 };
 
 ucc_status_t ucc_tl_mlx5_mcast_setup_rcache(ucc_tl_mlx5_mcast_coll_context_t *ctx)
diff --git a/src/components/tl/mlx5/tl_mlx5_rcache.c b/src/components/tl/mlx5/tl_mlx5_rcache.c
index 630a882f92..a2d1f10acb 100644
--- a/src/components/tl/mlx5/tl_mlx5_rcache.c
+++ b/src/components/tl/mlx5/tl_mlx5_rcache.c
@@ -55,7 +55,10 @@ static void ucc_tl_mlx5_rcache_dump_region_cb(void *context, //NOLINT
 static ucc_rcache_ops_t ucc_tl_mlx5_rcache_ops = {
     .mem_reg     = rcache_reg_mr,
     .mem_dereg   = rcache_dereg_mr,
-    .dump_region = ucc_tl_mlx5_rcache_dump_region_cb
+    .dump_region = ucc_tl_mlx5_rcache_dump_region_cb,
+#ifdef UCS_HAVE_RCACHE_MERGE_CB
+    .merge       = ucc_rcache_merge_cb_empty
+#endif
 };
 
 ucc_status_t tl_mlx5_rcache_create(ucc_tl_mlx5_context_t *ctx)
diff --git a/src/components/tl/sharp/tl_sharp_context.c b/src/components/tl/sharp/tl_sharp_context.c
index 91a4ddab5e..4401f7651d 100644
--- a/src/components/tl/sharp/tl_sharp_context.c
+++ b/src/components/tl/sharp/tl_sharp_context.c
@@ -261,7 +261,10 @@ ucc_tl_sharp_rcache_dump_region_cb(void *context, ucs_rcache_t *rcache, //NOLINT
 static ucc_rcache_ops_t ucc_tl_sharp_rcache_ops = {
     .mem_reg     = ucc_tl_sharp_rcache_mem_reg_cb,
     .mem_dereg   = ucc_tl_sharp_rcache_mem_dereg_cb,
-    .dump_region = ucc_tl_sharp_rcache_dump_region_cb
+    .dump_region = ucc_tl_sharp_rcache_dump_region_cb,
+#ifdef UCS_HAVE_RCACHE_MERGE_CB
+    .merge       = ucc_rcache_merge_cb_empty
+#endif
 };
 
 ucc_status_t ucc_tl_sharp_rcache_create(struct sharp_coll_context *context,
diff --git a/src/utils/ucc_rcache.h b/src/utils/ucc_rcache.h
index 1995e11ba8..9d8e5830c3 100644
--- a/src/utils/ucc_rcache.h
+++ b/src/utils/ucc_rcache.h
@@ -35,6 +35,13 @@ static inline void ucc_rcache_set_default_params(ucs_rcache_params_t *rcache_par
 #define ucc_rcache_region_put         ucs_rcache_region_put
 #define ucc_rcache_region_invalidate  ucs_rcache_region_invalidate
 
+static inline void
+ucc_rcache_merge_cb_empty(void *context, ucs_rcache_t *rcache,
+                          void *arg, ucs_rcache_region_t *region)
+{
+    return;
+}
+
 /* Wrapper functions for status conversion */
 static inline ucc_status_t
 ucc_rcache_create(const ucc_rcache_params_t *params,